By on July 14, 2015

original_bmw_battery

Last month, I shared the story of an unexpected double front airbag deployment in a BMW X5. In the twenty days since then, that car’s owner has been working with BMW NA, which conducted an independent examination of the car while it was in dealership custody. Yesterday he heard from a BMW consumer service representative, who told him that BMW has determined the reason for the deployment.

If this was Upworthy, or if we used the Upworthy Generator to create headlines, we’d have to title the article “What This BMW Representative Told A Father About His Airbag Deployment Will Break Your Heart. The Worst Part Is At 4:23 In The Call Record.”

But seriously, if you have a BMW you might want to click the jump, because there’s a good chance that BMW’s reason for the deployment applies to you as well.

The X5 owner shared a recording of his call with me. In the call, the BMW rep assigns the blame for the airbag deployment to the only non-OEM part in the affected chain: the battery.

“You had an aftermarket battery that was not installed properly,” she tells him. “The positive cable had a loose nut. This caused thermal events… thermal damage to the cable. There were several faults stored prior to the deployment. The airbag light was on in your vehicle prior to the deployment.”

The owner states for the record that he never saw an airbag light and that, had he seen one, he’d have acted.

“The battery wasn’t installed correctly,” the rep states later on in the call, “which caused a short. The battery cable began to melt. There are two scenarios that could happen. Number one is your vehicle catches fire. Number two is there will be an airbag deployment. There was melted plastic throughout the cable.”

I try not to wear too thick of a tinfoil hat nowadays, so my first impulse is to believe that BMW did, in fact, discover a loose nut connected to a non-OEM battery in this X5. What’s confusing me is:

  • Would a non-OEM battery with a tight nut also be a problem?
  • Would an OEM battery with a loose nut also be a problem?
  • Why would a loose nut cause the cable to melt?
  • Why would a melted cable cause an airbag deployment?

It turns out that there are two battery cables on the positive side of a BMW airbag. One of them has an explosive charge mounted on it. Supposedly, when the airbags deploy, this device “blows the connection” between the battery and the rest of the car to protect first responders. You can see pictures of this device on E90Post.

So, it’s easy to see the intended chain of events there and not so easy to see how the charge cable might cause an airbag deployment. Perhaps we have a BMW tech in the B&B who can elaborate further. In the meantime, if you own a BMW that was manufactured some time in the past twenty years, you might want to consider having the battery, and cable, evaluated by your dealership. Loose battery terminals are as common in a parking lot full of old cars as empty cigarette cartons, so the news that having one could lead to an airbag deployment is worrisome, to say the least.

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125 Comments on “BMW To Customer: Aftermarket Parts Cause Fires, Airbag Deployments...”


  • avatar
    Waterview

    Not that I needed another reason to not buy a BMW, but I’ll add this to my running list which now stands at 5,367 items. I’m all for protecting first responders, but I think zee Germans may have over-engineered this one a bit.

    • 0 avatar
      Lou_BC

      Unless BMW uses different technology than what I am aware of, capacitors are present in the electrical system that “store” energy to be used to deploy the airbags even if the battery is damaged in a crash. The risk of post crash deployment exists for quite some time post crash even with a “cut” battery.

      • 0 avatar
        El Hombre

        I did my first factory school air bag class in 1985. They mentioned the capacitors then, the service manuals advise to remove the negative battery cable and wait a minute for the caps to discharge before you start messing with the steering column. So when GM is being roasted for the ignition switch recall, supposedly because the air bags go dead when the key rotates to the off position, I’m wondering what about the caps? Still there? Or no longer used? Most cars won’t coast with a dead engine for more than 15 seconds; unless going down some monster downhill. So the car should be sitting still before the caps discharge and kill the airbags. I did some web search and couldn’t find a definite answer about the caps.

        It was a GM school btw…

      • 0 avatar
        MadHungarian

        Evidently not in Chevy Cobalts.

  • avatar
    Tstag

    Hmmm I can’t help but think that there is an engineering fault with the car myself. Surely the design should be more robust than this?

  • avatar
    Hummer

    “One of them has an explosive charge mounted on it.”

    I’m sure it’s safer than it sounds, but arent there better ways to drive up insurance costs?

    Maybe they can start bloodletting the driver before impact to help prevent some other issue.

  • avatar
    gtemnykh

    This kind of sums up modern BMWs, and German cars in general for me in one tidy anecdote.

    You can only have the dealer replace your battery with a special battery with German fairy dust, or else they will wash their hands of anything that goes wrong with your car.

    You can only use some particular fancy German approved synthetic oil, and there’s no dipstick to double check against the sensor.

    You will have 10+ stored fault codes after 5 years of ownership.

    One used to buy German cars for their solid highway poise and quiet ride, and dealt with all the BS because nothing else could match their autobahn tuned performance. That is no longer the case, they have no excuses.

    E53 X5s and even moreso their E70 successors seem to be some of the most troubleprone BMW models, not sure if their South Carolina provenance has anything to do with that.

    • 0 avatar
      Roberto Esponja

      Amen, gtemnykh. I got so incensed when I realized that, in order to replace a burned-out parking lamp in my wife’s 2008 ML550 I would have to remove the entire bumper fascia. I couldn’t believe it! It’s like they purposely design everything so as to make it impossible for the owner to service anything. No more German vehicles for me…

      • 0 avatar
        LeMansteve

        Engineering compromises exist in every brand. Some can make basic maintenance very difficult. Keep in mind, GM full size SUVs also require bumper cover removal to replace a simple headlight bulb.

        BMW oil filters are removed easily from the top of the engine. Honda oil filters are mounted to the block, underneath the car.

        • 0 avatar
          Roberto Esponja

          Stop the insanity!

        • 0 avatar
          bball40dtw

          Many cars are like that now. The HHR required bumper removal to replace a bulb. On the Fusion, Ford recommends bumper removal. There used to be a panel in the wheel well that had access but I don’t think it’s there on 2013+ Fusions.

          • 0 avatar
            CoreyDL

            On my previous GS, I had to replace a brake lamp bulb once. Being accustomed to zee Audis, I thought “Oh good, I’m going to need a special German tool, and remove the trunk liner and some protective rear fender plate.”

            But no, there was a special plastic panel which covered the rear bulb assembly area, which was removed by hand with a big plastic screw knob. Took all of three minutes.

            Thanks Toyota, doing it the practical way makes sense.

        • 0 avatar
          Lou_BC

          LeMansteve – agreed. All I have to do is ask my brother about changing bulbs on his Sierra HD company truck to get the blood vessels popping out of his head.

        • 0 avatar
          gtemnykh

          I agree that I’m generalizing, and yes older Hondas and their rear mounted filters are a pain. Likewise my old 4Runner. Everything else is a peach to work on, but oil filter access is through the driver’s side wheelwell, and inevitably oil spills all over the skid plate and then drips on the ground for several days after that. Newer Subaru FB25 engines likewise have the top mount oil filter, seems like a no-brainer IMO.

          It just seems that the Germans give themselves way more lee-way in giving DIY and non-dealer service much less thought. Additionally, their designs strike me as less robust in that they are more finicky with fluids/batteries/etc, and more susceptible to heat and poor road surfaces. Add to that more overall gadgets to break, and comprehensive diagnostics systems that track things like whether a trunk light is out, and you end up with fairly new, low mileage cars that spit out a long list of faults when you hook them up to a scanner.

          • 0 avatar

            Long ago had an 86 Camaro that I needed to change headlight on.
            As far as I could tell,I needed to remove bumper…except,the bumper was one of the plasticy things and by shoving down on the plastic I could get the headlight out and replace it.

        • 0 avatar
          EAF

          This topic is my biggest pet peeve and an integral part of my research before making a purchase. It is the reason why I absolutely despise all that is VAG and why I will not own any BMW post e46 ever again.

          Steve, I would rather unscrew a traditional style oil filter on a Honda B series engine, from underneath & back as you described, than deal with BMW’s oil filter housing lid. I’ve seen many people cross thread these lids and they become brittle over time. You also have to replace the 2 internal o-rings; it is just messier IMHO.

          As far as I’m concerned, Honda and Toyota engineer cars that are easier to repair and that is important to me. It should also be important to you if your repairs are out of pocket.

          P.S. I’ve had BMWs with low voltage exude chaos with modules, air bags included, never a deployment however.

      • 0 avatar
        CoreyDL

        A used ML430 was on an article by Yahoo yesterday, as one of the coolest cars you can get online for under $5000.

        …Along with a CL500 which needed replacement ABC shocks.

        Srsly. I wanna slap these people.

        https://www.yahoo.com/autos/s/8-coolest-cars-under-5-000-133010558.html

        • 0 avatar
          PrincipalDan

          Now that Cadillac is using “MagneRide” on everything, how many hooptie owners are going to be able to afford those replacements?

          • 0 avatar
            CoreyDL

            You can probly fix it wit sum magnicks from AutoZones mah dood.

          • 0 avatar
            indi500fan

            There’s pretty good volume sales of resistor pack plug-ins to let you use basic old hydraulic shocks and fool the computer that there’s a magneride still there.

      • 0 avatar
        MBella

        You don’t have to take anything apart to replace a parking light bulb on that generation ML. The come out pretty easily. For the sidemarkers, you have to pull out the front fender liners.

      • 0 avatar
        cimarron typeR

        I have an 08 ml, I think this bulb can be changed with a long needle nose plier, if its the bulb I’m thinking of, MB forums has a how-to iirc
        I did have to change to battery which is under the passenger front seat, in 30 degree weather this past Jan. at an Autozone, salesman told me that their free installation didn’t apply to certain makes. I may pay an indy next time.

      • 0 avatar
        Jack Denver

        This has been going on for a long time. I had a ’99 Audi A6 and the only way to get to most of the engine components was to remove the front bumper and radiator. It was #2 in most service procedures, right after “Disconnect the negative battery terminal”. I don’t even know why they bothered with a hood since there was hardly anything accessible from the hood. When you opened the hood, there was another hood (plastic cover) covering the top of the engine. You as the owner were never supposed to see the actual engine.

  • avatar
    Cabriolet

    I have just gotten finished going over a 25 year old German car that also has a airbag installed. The wiring was fine but i did come across a few ground connections that were not too well grounded. After cleaning up these poor connections the car ran 100% better. Started faster, ran smoother and idled like the day it was built. In the northern states of the USA the use of salt to keep the roads clean can create a mess of the cars wiring. Most manufacturers do not protect the ground connections in their vehicles to prevent corrosion and after a couple of years in damp salty conditions these connections can create many problems. A computer must have a perfect ground connection and if not will look for another connection to ground it’s self. I hate to think of these modern cars being on the road 10-15 years from now without someone checking the electric system. Some people are going to face fires, dead computers and airbags that will go off by themselves.

    • 0 avatar
      Hummer

      That’s why I stick with my belief cars(trucks) (American at least) made between 2000-2010 are the high point of advanced technology with simple design and with ease of servicibility by anyone with a mechanical inclination.

      Granted, I’m sure someone older than me has probably said that about a previous decade of cars.

      • 0 avatar
        RideHeight

        “someone older than me has probably said that”

        Yeah, I did.

        “Hell, I just installed manual chokes and I could start anytime, anywhere without all this goddam computer-controlled-interlocked-everything sh1t! Eff the environment! Breed fewer people!”

        Said it a couple of days ago.

      • 0 avatar
        davefromcalgary

        My 02 Alero, I could replace the entirety of the exterior light bulbs using just my hands, no other tools, and the oil filter was top accessible and leaked not at all when removed.

        Fricken loved that about it.

  • avatar
    sportyaccordy

    That’s a real shame. E90 335i sedans are getting cheap. I suppose they will get cheaper now as this news spreads.

  • avatar
    Kato

    I’ll state the obvious. A loose battery terminal would cause high resistance not low resistance. For a short circuit to cause resistive heating, you need a “circuit”, i.e., something on the other end of the battery cable had to complete the circuit to ground, and the resulting high current would then cause resistive heating. I hope the owner took lots of high-res photos before the dealership got their mitts on it.

    • 0 avatar
      White Shadow

      You are exactly correct…high resistance…which will lead to heat. Here’s the rub though–just about every circuit in the car “completes” through the ground cable attached to the battery. So plenty of opportunity for electrical gremlins to pop up with nothing other than a poor connection such as a ground (or power) cable.

      Many years ago my dealership had a guy come in with a strange problem. Whenever he stepped on the brake pedal, the FM stereo would stop playing. It would play fine once he took his foot off the pedal. Strangely, this did not happen when he was listening to AM radio. He could listen to AM uninterrupted no matter how many times or no matter how long he had his foot on the brake pedal. Other shops had tried everything from replacing his radio to replacing his brake switch in an effort to solve his problem. Nothing worked.

      So what was the problem? Simple–it was a loose ground. The brake circuit and the radio circuit shared the same ground. The ground connect was loose enough that it couldn’t support the brake lights and FM radio at the same time. AM radio, however, requires fewer amps, so the radio would continue playing an AM with the brake lamps illuminated.

      Anyway, my point is that there are a few people here who obviously don’t understand vehicle electrical systems (and don’t even get me stared on airbags–they are among the most misunderstood systems on modern vehicles) and therefore can’t fathom how something as simple as a loose battery cable can cause havoc on a modern car.

      • 0 avatar
        panzerfaust

        Yep. I used to have a T-bird that would go through ignition control modules and batteries like clockwork. It wasn’t until I replaced the alternator and was talking to a retired Ford mechanic that he told me to replace the ground cable, which was 6 feet long, and had an extra strap that grounded to the body along the way and when that was corroded, (which it always was) the electrical problems started. Once the ground cable was replaced, no more of the usual problems.

        • 0 avatar
          sportyaccordy

          I replaced the starter to ground cable on all 3 of the Accords I owned. Short cable…. probably like 7 inches, but thick and insulated so it would corrode like nothing and lose its ability to pull the current it needed at the right voltage. Saved so much money on batteries. Ground wire kits really worked back then…

      • 0 avatar
        krhodes1

        Most dealership technicians don’t understand electrics. This is 99% of the reason for “unfixable cars”. There is a loose ground or somesuch somewhere, but they don’t have the first clue how to find it (and can’t read a wiring diagram), so they just keep trying to fix the parts that are affected by this without finding the root cause of the problem.

        I clean grounds as part of my annual maintenance afternoons on my cars.

  • avatar
    LeMansteve

    If the root cause was a loose terminal, the brand of battery shouldn’t matter. These are basic sealed lead acid batteries. Nothing fancy. A loose connection would cause an increase in resistance and therefore an increase in heat. Correct?

    Now consider the numerous electrical systems in this car have gone through 13 years / 155k miles of heat cycling. It seems reasonable that they would be more sensitive to any voltage or current irregularities.

    Also, I’m not sure what the lead picture is supposed to imply. Just because the battery was made by the OEM, does not mean it was made to the OE BMW specifications.

    I hope he didn’t also have to replace his Battery Safety Terminal (BST). On the E46, they run about $500, with no aftermarket version. Genuine BMW only.

  • avatar

    Their response seems very generalized and I don’t see how it could have caused the airbag to deploy. The pyro connection is called the Battery Safety Terminal (BST) and is intended to blow in an accident so that the car doesn’t catch on fire. There are lots of other cars that have similar connections either to cut off electrical or cut off fuel in the event of an accident.

    I have seen damage to the BST happen from car audio installers that are not informed where they take the terminals apart and add a wire for an amplifier causing the BST to blow. In those cases, the entire cable with the BST has to be replaced but it would still not cause an airbag deployment.

    In most cars, if the airbag light is on the SRS module disables the whole system for safety so that is another suspicious point. I would be interested to know whether the owner has any aftermarket audio or electrical components installed and what type of battery was in there. Also, if the airbag light did not come on I wonder if it comes on during start up at all or if the light has been disabled.

  • avatar
    bullnuke

    Sounds similar to my experience with American Honda years ago. “The vehicles we manufacture are perfect in every way. Your problem was owner abuse in that you did not come to your authorized Honda dealer for oil changes, tire pressure checks etc. at the recommended intervals and you performed these very very technical procedures yourself. Nor did you faithfully support your authorized Honda retailer’s bottom line with payment of his exorbitant charges for servicing your vehicle to accomplish these very very technical procedures. Oh, and by the way, we have more lawyers than you can afford and will easily prevail in any denial of warranty claims.”

  • avatar
    Athos Nobile

    “Why would a loose nut cause the cable to melt?”

    In my experience, a loose connector on a cable that carries a lot of current will create a hot spot. I saw this happening at 350-400A AC. It is probably related with the reduced conductor contact surface. It seriously oxidise the copper and cooks the insulation.

    350-400A AC will loosen a connector, so you have to be on top of it.

    A car environment has a lot of vibration and temperatures changes on top of the current carried.

    “Would a non-OEM battery with a tight nut also be a problem?”
    “Would an OEM battery with a loose nut also be a problem?”

    If the issue was the fitment / low nut torque, I cannot see how using an OEM or aftermarket battery of the same type would make any difference, unless, that is, the aftermarket battery makes it easy (for whatever reason) for the nut to go loose.

    From the pictures on that forum post, I would question if the nylock nut was replaced when the new battery was fitted and if the proper torque was applied to that joint. I am talking about that picture in particular.

    In any case, if it was improperly installed, it should fail with either an OEM or aftermarket battery.

    Looking around, I found the link below. Battery cables are ~ 2 or 4 size, maybe even bigger. That’s a lot of current.

    http://www.trojanbattery.com/pdf/WP_BatteryCableGuide_0512.pdf

    From the (limited) explanation you posted, I cannot figure the failure mode.

    • 0 avatar
      krhodes1

      And modern BMWs have 250A+ alternators. Part of their “Efficient Dynamics” efficiency package is that the alternator basically only charges the battery when the car is coasting. So when it IS charging, it is pumping some serious amperage into the system. This is also why they have the requirement for “battery registration” – the system needs to know the type and age of the battery to prevent overcharging it. Replacing the battery and not registering it can cause VERY BAD THINGS to happen.

  • avatar
    Audiofyl

    Many of you probably changed your own battery at some point in the past. If you remember, it’s very likely that when you made the final connection to the battery, a small spark was generated as the systems in the vehicle that keep memory are charged back up are regaining power. That small spark will leave a small black char mark on the terminal and the battery post. Should the terminal be left loose, it can make continuous small Sparks and even some larger ones when higher current is required (i.e. Starting). Over time this can generate significant heat due to arcing and more so due to a higher resistance, as has already been mentioned, from a lousy connection that isn’t fully metal to metal. These factors can easily add up to a very melty battery cable and whatever else may be attached to it in the immediate vicinity.

    • 0 avatar
      danio3834

      The technical term for this is “terminal fretting”. A lot of electrical issues in vehicles are caused by this occurring in any number of connectors throughout the vehicle.

    • 0 avatar
      fvfvsix

      You think it’s bad in cars… I’ve had it happen to my home recently, when the idiot electrician who installed my breaker panel left off a nut connecting the main breaker to sub breakers. It fried thousands of dollars of electrical equipment by the time we found the issue.

      • 0 avatar
        panzerfaust

        Wow, and I thought finding an outlet box duct-taped in place, and another nailed in place with the nail through the box and the wires was bad. (this was by the crew that built the house).

        • 0 avatar
          CoreyDL

          When my dad opened up a wall in my house (from 1938) he found the pipes running from the bathrooms down to the basement went every which way and snaked around in the wall!

          The builders/plumbers used whatever pieces of iron pipe they had available, which apparently on that day was not straight pieces. Way easier than going down to the supply depot, I reckon.

          • 0 avatar
            PrincipalDan

            A friend opened up a wall in the 50 year old house he was living in (former family home, parents died, passed through the hands of many relatives, back to him, yada yada) and found the last 12 inches of pipe leading to a natural gas wall furnace was galvanized water pipe!

          • 0 avatar
            SP

            The twisty pipes may possibly have been intended as a primitive pressure relief loop to reduce water hammer. Just giving our ancestors the benefit of the doubt here.

          • 0 avatar
            CoreyDL

            Ahh, didn’t think of that. I shall pose that to my dad.

  • avatar
    PRNDLOL

    BMW Bangerz

  • avatar
    wmba

    Nice for the BMW rep to tell their customer that the airbag light was on, when it was not. Probably happened an instant before the airbags deployed.

    High resistance connections can easily cause a fire – that is hardly news. I have seen one happen right in front of me to my initial complete disbelief that it was indeed happening. The insulation can become so hot it melts or actually catches fire. All along the cable, though? No,just near the heat source in this scenario.

    A loose nut obviously could allow a high-resistance connection to develop. Usually, battery posts are slightly tapered, so good connections can be made with a slack nut and last for years, so long as the connector doesn’t back off the post at all. The really high current draws only happen when the starter motor operates, and that generally is only for a couple of seconds, so nothing much happens to heat anything up.

    How the airbags could or would deploy in this scenario is something only BMW could answer. They assert it to be so. I would not take their word for it unless a rational reason were given. Also, if it were a possibility, BMW should have a printed alert CAUTION warning of this scenario at the battery to warn that connections MUST be tight.

    I thought you had to get a new battery from BMW to avoid a CEL, though what checks occur to ensure it’s a genuine Bimmer one I do not know.

    Then again, BMW has abandoned the oil dipstick for years as well, and I’ve personally met a poor bastard who had to have his brand new 2007 wundercar shipped 275 miles twice to the nearest dealer when a low oil level warning went off. I met him on the second occasion when he was wandering around town killing time, and he was a decidedly unhappy camper.

    Then there’s the run-flat tires.

    The suggestion that owners check their battery connections is a good one.

    • 0 avatar
      LeMansteve

      “I thought you had to get a new battery from BMW to avoid a CEL, though what checks occur to ensure it’s a genuine Bimmer one I do not know.”

      You are referring to the Absorbent Glass Mat (AGM) batteries, which must be “registered” when installed. AFAIK, only the dealer can perform battery registration. These are not drop-in DIY battery changes. I think the first BMW to use an AGM battery was the E65 7-series.

      This particular X5 came with a lead acid battery from the factory and not an AGM battery. The 2nd-generation X5, the E70, was when BMW switched to AGM batteries on that platform.

      • 0 avatar
        vvk

        Anyone with a $17 cable from eBay can do battery registration. I am so tired of people bringing this up.

        I have an app on my phone that can do a battery registration using a $5 bluetooth adapter.

        • 0 avatar
          wmba

          @vvk

          As I do not own a BMW, why in heaven’s name would I know about some obscure gadget sold on eBay that gets around the battery registration process BMW created for the E70 and newer? Most things people think of as common knowledge are in no way so arcane as your example. Like cereal becomes soggy when left in milk too long – that’s well-known.

          I don’t know BMW’s platform numbers either, and am much happier for not cluttering up my mind with such minutiae. I clog up my mind with minutiae that has meaning to me.

        • 0 avatar
          RideHeight

          “Anyone with a $17 cable from eBay can do battery registration. I am so tired of people bringing this up.”

          God, seriously! The two guys painting upstairs right now, Ray and Arturo, were going on about that yesterday.

          Trapped in my basement, I had no choice but to listen.

        • 0 avatar
          LeMansteve

          Excellent. I figured there would be some aftermarket workaround.

      • 0 avatar

        And here I’d thought that BMW didn’t start using the AGM batteries until the F01 (2009 and later) 7-Series, and all of the later F cars.

        I’d been considering purchasing a pre-owned E70 X5 for business use; we’ll just chalk this up as another reason not to get one. Maybe I’ll just get a Tahoe and be done with it.

        • 0 avatar
          CoreyDL

          Lexus GX!

          • 0 avatar

            That’s another option. A friend of mine’s father has a 2004 GX 470 that he bought new, having taken advantage of the lucrative tax credits offered on heavy vehicles at that time. The transfer case busted earlier this year, while he was out of town, and had to be replaced, but that’s the only time it’s left him stranded. If he’d had a BMW, I’d surmise that it’d be gone by now.

            I’m trying to juggle needs of dependability with the features, design and handling that I’m used to with Euro cars. So I’ve been trying to convince myself that an E70 X5 is a rational decision and that it won’t cost me a fortune to keep…

          • 0 avatar
            CoreyDL

            “features, design and handling that I’m used to with Euro cars.”

            Well this eliminates the Tahoe, and would leave the GX and the X5 in this scenario! But the X5 will always be a money pit, surely enough. And that 4.7 is a great engine, and it’s not like you’d have to seek out a well-optioned example like you do with the X5.

          • 0 avatar
            fvfvsix

            @Kyree – A Lexus GX would indeed be a handling tradeoff, but IMHO the assembly quality of those vehicles is taken to the level of high art. If you are considering a business vehicle, you should seriously consider one… or go straight for a LX, which is indeed the bee’s knees.

          • 0 avatar
            CoreyDL

            Considering he’s buying used, I’m guessing price is of importance here. The GX, X5, and a nicer Tahoe would be about the same price. The LX is another 10 grand at LEAST, if you want an equivalent year to those other three. And the Land Cruiser isn’t much cheaper.

        • 0 avatar
          KevinC

          My E86 Z4M Coupe had an AGM battery from the factory, but it doesn’t require registration, as the electronics in the Z4 are the same as the E46’s.

      • 0 avatar
        Marko

        Mercedes has used AGM batteries for more than a decade, yet they do not require “registration”.

      • 0 avatar
        Lack Thereof

        Although I know nothing about “battery registration” (how does the car know what battery is in it? AGM batteries all make the same 12.8v), AGM car batteries are available at most chain auto-parts stores.

        When I was an Autozone manager, we sold quite a few of them… although the top-grade wet batteries seemed to outlast the AGM’s, and thus came with a longer warranty. And most of them we installed in the parking lot, in the trunks of BMW’s and Mercedes’.

    • 0 avatar
      White Shadow

      As the owner of a few different new “dipstickless” German cars, I can tell you that there is usually a warning when the oil is low, but not at a critical level. My Audi will flash a message that the oil level is low, but that driving the car is okay.

      Anyway, that guy with the 2007 BMW should have had a similar warning that the oil was low. And that warning is just a warning–not that the car can’t be driven. Either way, after the first time he found himself needing a tow, he should have learned his lesson and kept a quart of oil in his trunk.

      • 0 avatar
        CoreyDL

        Here’s a question or four:

        -What kind of product excellence/quality is the manufacturer providing to the customer, where creating a car without a dipstick is preferable to a car -with- one?

        -How is this an acceptable engineering solution?

        -How do the makers doing this “sell” it, or pass it off?

        -Which makers did this, and for what time period?

        • 0 avatar
          Jack Denver

          Dipstickless cars have oil level sensors instead. I could see how a sensor could be just as good or better than a dipstick. For one thing, you actually have to open the hood and check the oil with a dipstick – I’ll bet you a very high % of owners NEVER check their oil. If the vehicle is leased, even more.

          In the situation described, the oil must have fallen below some critical level (probably after the warning light had been on for many days or months) and the engine shut itself off to protect itself from severe damage. For every false positive (engine shuts itself off even though there is plenty of oil) there are probably 100 engines saved by this sensor.

          • 0 avatar
            CoreyDL

            Yes, you don’t have to raise the hood. But the car has to have a functioning battery and ignition system, and be running to tell if there’s a problem. I can lift the hood at any time, even if there’s no battery in the car.

            Just seems silly not to offer both, or engineer out something so simple.

        • 0 avatar
          panzerfaust

          They probably figured since there’s a dipstick behind the steering wheel, the one under the hood was redundant. (sorry, couldn’t ‘resist’ that one!;)

        • 0 avatar
          beastpilot

          The upside to battery registration? The battery in my wife’s ’04 E46 is still original and has over 50% capacity left. The one in my ’08 E60 is doing great too.

          Error codes in a BMW are stored with the mileage number. You can easily see how long ago a code was thrown and when a light came on.

        • 0 avatar
          beastpilot

          I actually much prefer to be able to check my oil from the dash anytime I am in the car. I can see it anytime I want.

          The car doesn’t need to be on or running to do so- it’s smart enough to store the last value from shutdown and I can pull it up even without the key in.

          When I need to add oil, it literally says “Add 0.7 quarts”. Even better than looking at a dipstick and iterating over and over to add the right amount.

          So, there’s only two places it’s an issue:

          1) Just did an oil change. But I’m smart enough to count 8 quarts, then fire it up, and let it tell me “Add another 2.3”. You have to fire up your dipstick car too in order to get the oil into the filter before your final read.

          2) You got a car you know nothing about that was trailered to you. The oil might have been drained. The battery is dead. OH MY GOD CAN I START THE ENGINE OR AM I OUT OF OIL?

          Yeah, replace the oil in the car at that point. You have no idea how old it is anyway. This has happened to what, one person ever?

          Is the car without a dipstick preferable? Not really. Is it worse? Nope, it’s the same- has some upsides and some downsides. I hate checking the oil on my cars with dipsticks (paper towels, dirty hands, mess, hard to read with clean oil). So I do it a lot more in the car that is automated.

        • 0 avatar
          White Shadow

          According to Audi, the reason is that their customers just don’t want to pop the hood and pull a dipstick out, wipe it down, reinsert it, pull it back out again to read the oil level. They’d rather press a button and read a graphic representation on a screen. And the electronic sensor is actually very accurate. I’ve tested it myself during an oil change by adding the final quart 25% at a time. It was dead on.

          But at least with Audi, the dipstick hole is in place, for technicians to use during service. Owners can buy a dipstick from the dealer if they really need to have one. I had planned to do that myself, right up until I discovered just how accurate The electronic sensor reads out.

          • 0 avatar
            Power6

            I don’t know if this is true or not, but I read when GM removed the dipstick from the Cavalier automatic transmissions (and left no way to check it other than fill hole below) the reasoning was that their research had found, most of the contamination of the trans fluid, was introduced through checking the trans oil so removing it extended the life of the fluid. Again no clue if that’s true but I do distinctly recall reading it.

  • avatar
    danio3834

    I have seen all manners of problems in vehicles caused by non-OEM spec or defective batteries. If the battery meets all the OEM specifications, it *should* perform the same. However some cause wonky electrical issues due to poor voltage regulation, for example a Focus with unintended ABS activation when braking. Poor connections can have the same effect. So without speculating too far on this case, I won’t say their explanation is impossible.

  • avatar
    SCE to AUX

    A loose connection is:

    1. Not due to an aftermarket battery. It’s a labor problem.
    2. Not the same as a short. I don’t know why they used that term, except to scare the customer.

  • avatar
    vvk

    The lesson here is that people should inspect and tighten up their battery cables on regular basis. This has nothing at all to do with BMW as a brand.

  • avatar
    Land Ark

    My wife’s 2006 Z4 just went through this.

    Her oem battery died after 8 years in service and a lengthy period of disuse with the battery connected. No issues with that.

    so, instead of going to the dealer for a new battery (because who does that?) we picked one up from the aftermarket. After about 6 months and ~100 miles that battery drained. I charged it up and the airbag light came on. This was not as a result of a loose nut as I tightened it down myself and it was not loose.

    After some research I discovered this explosive charge on the cable thing. I basically read everything you just transcribed.
    I also saw that there were only something like 3 manufacturers of batteries for her car who sell them to dealers and other companies who rebrand them.

    My wife took it to the dealer once the battery was fully recharged to have the airbag light turned off. They said that the fault was caused by the aftermarket battery and convinced her to replace it with an oem battery. I don’t recall them telling her the airbags could deploy due to this issue but there was concern about the cables melting.

    This was also when they talked her into replacing her rear brakes which, based on my having her bring the old parts home, was completely unnecessary. So the dealership makes it difficult to believe anything they say much to their and their customers’ detriments.

    • 0 avatar
      Exfordtech

      After a lengthy period of disuse, followed by ~100 miles in 6 months, what condition were the rotors in? Corrosion buildup on the exposed rotor surface (on 8 year old rotors) can cause an uneven braking surface. This effect is more pronounced on rear calipers that apply the pads directly to the rotor for the parking brake, as that part of the rotor is somewhat shielded from ambient humidity. Not saying the dealer was right, just playing devil’s advocate. What was replaced?

      • 0 avatar
        Land Ark

        The car is stored year-round in our garage which is semi-climate controlled. She also never drives it in the rain and rarely washes it. There isn’t even rust on the parts that don’t come in contact with the pads.

        They replaced the rear rotors and brake pads.
        I should also mention that the car has less than 40k miles on it and she had the “Level 2,” or whatever, service done the previous year without mentioning the rear brakes and she’d driven maybe 1,000 miles in that time.

        I have to say, I was pretty upset when I saw them. There was no odd pattern on the rotor surfaces, I could barely get my fingernail to grab an edge, and I’ve put new pads on a car with less meat on them.

        • 0 avatar
          Exfordtech

          Well that sucks. I’d be willing to bet that magical “level 2” service included several dubious items that go above and beyond the factory maintenance schedule. This is a classic dealership ploy to extract more money from you than actually necessary. Because so few vehicle owners open (never mind read) their owner’s manual, they fall prey to the additional “recommended service” that they say is needed “due to the unique driving conditions of our area” or other such nonsense. RTFM absolutely applies to an automobile’s maintenance schedule.

  • avatar
    DenverMike

    We know the the front airbags are directly interconnected to the positive battery terminal since the front airbags normally trigger and set off that “positive terminal” in the event of an accident.

    So who says the ‘trigger’ signal can *only* flow from ‘front to back’ and not ‘back to front’ when the “positive terminal” detonates itself? There should be a safeguard or a one-way diode, but who says it’s there??

    • 0 avatar
      Audiofyl

      While what you said was sort of true, it doesn’t really work that way. The car has an air bag controller that is a somewhat separate system from everything else. Yes it is partially interconnected in that it needs input (speed, ignition, seat sensors, etc). However it is the module that sends the signal to the airbag igniters, seat belt pretensioners, and also the battery terminal disconnect, all via separate cables, to tell them to deploy/ignite. That is why not all the airbags deploy at once depending on the crash situation (or lack thereof in this specific case). At any rate, the signal doesn’t come from the airbags or from the battery disconnect, but the control module that determines when/if any of these items should be ignited.

      • 0 avatar
        DenverMike

        It was no a coincidence, there has to be ‘trigger’ connection, direct or indirect, from the positive terminal device to the passenger airbags. The terminal detonating itself, without prompting from the control module, is not an event that’s *designed* to happen. So what if it does happen?

        The question is, can the ‘positive terminal device’, if setting itself off, inadvertently deploy the ‘passenger airbags’, and was there a safeguard designed for such an event? Clearly it can and there wasn’t.

        Are the airbags and positive terminal device designed to work independently? Why would they? And is there a reason to have the trigger “signal”, which is just a 12v input, to only go one-way? Is there a reason to have both terminals/leads isolated within the module? Obviously they’re not.

        It’s just a simple oversight by engineers.

        • 0 avatar
          PrincipalDan

          Makes me think of one of the two recalls I had on my 1997 Ford Escort wagon. There was a recall to inspect and then shield the airbag sensors in the front bumper area because they had been installed and engineered in a way that left them susceptible to corrosion. Corrosion would cause a short and set off the airbag.

          Ironically I received the recall notice right after moving to New Mexico (land of little corrosion) from Michigan (land of much corrosion.)

        • 0 avatar
          Audiofyl

          depends on how the airbag control module is designed. if repeated voltage spikes from the arcing battery terminal are causing it to be damaged, then it is completely independent of the battery safety terminal (BST) and the airbags blew because the potentially damaged control module thought there was a fault when indeed there wasn’t, causing the airbags to deploy as well as the BST. That doesn’t mean the BST caused the inappropriate deployment just because it is attached to the positive terminal. Additionally, we don’t actually know the exact series of events so we are both speculating from opposite sides of the situation.

          • 0 avatar
            DenverMike

            Let’s not read more into it than what’s there.

            There’s no reason to deduct the airbag control module was damaged in any way by arcing at the battery. It’s far removed. Unless you’re thinking there’s a control module on the positive terminal. There’s not.

            Otherwise, inadvertent passenger airbag deployment would be common to all cars and trucks with battery connection issues. They don’t.

            The problem was isolated between the battery and positive terminal (BST). A meltdown you could say. So the BST deployed itself. Everything it needs to do so is right there on the terminal.

            There’s not a *smart* deployment signal/trigger that sets off an airbag. There’s no way for an airbag to know where the trigger originated. Just 12v.

          • 0 avatar
            fvfvsix

            @DenverMike
            It’s totally possible for an airbag controller to develop a damaged power supply because of arcing at the battery terminal. If not designed impeccably, it would work right up until it delivers some brownout condition at the airbag controller MCUs that cause their software to go in to “crash mode” routines.

          • 0 avatar
            DenverMike

            Anything’s possible, yeah. We’re just talking what’s most likely happened, based on what we know. It’s not a court of law.

            But what is “arcing”? Is it not just regular voltage forced to jump gap creating heat enough to weld? More than enough heat to fuse wires together, inches from the arcing. The control module has to have protection besides the 100 or so feet of wiring.

            OK we know what detonated the positive terminal and some kind of 12v signal was sent to the control module, where it shouldn’t. Like to an input to an output that the module wasn’t programmed to receive. Meaning if airbag trigger and the positive terminal trigger should leave the same port (In a serious enough accident) on the control module. Power/signal went in where it shouldn’t and came out where it shouldn’t. This with the control module unaware anything popped.

          • 0 avatar
            Audiofyl

            @DenverMike

            we don’t actually know the BST was blown. No where did it say that I can see in the article above. Yes it was mentioned by the author that it exists, and that it is supposed to disconnect when the airbags deploy, but it doesn’t actually say in quotes from the recorded conversation that it was detonated, so that, too, is speculation.

          • 0 avatar
            DenverMike

            We do know there was a “thermal event” in the BST, then the passenger airbags deployed. Even of the BST itself deploy, the (faulty) message was sent forward to the passenger airbag to deploy, even if indirectly.

            Regardless of how/what/why, the 1st event caused the passenger airbags to deploy. You can’t get around that fact.

        • 0 avatar
          White Shadow

          Read up on airbag “safing” sensors.

  • avatar
    Exfordtech

    “You had an aftermarket battery that was not installed properly” places the blame on the installation of the battery, not the battery itself. Otherwise BMW would be running afoul of the Magnuson-Moss act. I presume the chain of events is poor connection leads to overheated battery cable, melted insulation created a short to ground, attendant voltage spikes resulted in airbag deployment? I guess it’s possible, but I think I might be contacting a lawyer (is Ralph Nader still around?). As for the airbag light being on, does the module record the length of time the light was on? I can’t say for certain, but I would be surprised if a loose positive cable wasn’t causing other symptoms such as hard starting, battery/charge light flickering.

    • 0 avatar
      Jack Denver

      Then why did they mention “aftermarket”?

      The failure point in most modern accidents is human caused – either (mostly) a human driver who directly caused the accident or failed to maintain the vehicle or hung 99 keys from her key ring, etc. or a different human who installed something wrong. The number of instances where a product was truly defective and did not give warning prior to the accident is miniscule.

      It may seem like “blaming the victim” for BMW to say that the terminal was loose, the light had been on but had been ignored, etc., and maybe it isn’t even true in this case, but working with consumers can make you cynical because they do so many incredibly stupid things so often. If you hear hoofbeats you are supposed to think common horses,not rare zebras and the most common hoofbeat is that of human stupidity.

  • avatar
    Da Coyote

    Again, my experiences with my ’11 Benz showed me that the Germans and electronics are not friends. Stories about Audis and Volkswagons appear to confirm.

    I ditched the Benz after two years of problems (thank God for warranty). Never again.

  • avatar
    PrincipalDan

    The rooster crows immediately before sunrise, therefore the rooster causes the sun to rise.

    Post hoc ergo propter hoc

  • avatar
    WhiskeyRiver

    “Aftermarket Parts Cause Fires, Airbag Deployments.”

    This, as opposed to genuine OEM BMW parts installed at a dealership?

    I wonder which avenue produces the most spectacular fire. Aftermarket or OEM?

  • avatar
    CJinSD

    Did the pyrotechnic battery cable deploy with the airbags? If it did, then the explosion would be a plausible explanation for melted insulation. People that are making excuses for BMW are at risk of doing something so ironic that it won’t be ironic at all.

  • avatar
    Master Baiter

    If the battery cable is loose and the battery is charging, you could have high voltage spikes on the B+ line due to the alternator running with the battery load coming on and off line. This could set off the airbag or damage the controller. Perhaps the OEM battery has a more robust connection point that is less likely to come loose. Just a theory…

  • avatar
    APaGttH

    Could you just imagine the brain meltdowns if you swapped out BMW and replaced it with FCA, Ford, GM or say a maligned brand like Mitsubishi?

    • 0 avatar
      bball40dtw

      ACTIVATE CONGRESSIONAL HEARING!

      • 0 avatar
        APaGttH

        Exactly.

        The wails of the stupidity of this design would be deafening if it had come from anywhere else but Germany that includes Japan.

        BMW ceased being the “ultimate driving machine” years ago and the X5 from a quality stand point has always been a bit of a hot mess.

    • 0 avatar
      CJinSD

      I like that you think it has to be one of the UAW-3, but people would freak if this were Toyota, Honda, Nissan, or Hyundai too. Actually, haven’t some F150s had mysterious airbag deployments without publicity?

      How about GM refusing to recall 200,000 self-immolating Hummer H3s? Think it will merit a story? You can pretend that you believe Toyotas really accelerated on their own again!

      • 0 avatar
        APaGttH

        I didn’t know Mitsubishi is from Detroit, you have a reading comp issue CJ. Oh, and TTAC covered the Hummer recall story – and the I hate Toyota meme is really, really, old.

        You need some new material. You’re boring me —

  • avatar
    PriusV16

    What I always say:

    German cars. If you’re too cheap to always have them maintained by an official dealership, then don’t drive ’em.

    • 0 avatar
      Jack Denver

      I kept a 99 Audi until this year and from the day that the warranty expired until the end, it never again saw a dealer’s service dept. Anything that I did not do myself was done by an independent shop that specialized in VW/ Audi products. Before that I had a BMW and a mechanic who specialized in those. The only thing the dealer has is higher prices. A good independent knows as much or more than the dealer monkeys.

    • 0 avatar
      panzerfaust

      Yes, that. Nothing more expensive than a cheap Mercedes.

  • avatar
    hawox

    almost every cars has safety switch on the battery.

    • 0 avatar
      redmondjp

      What country do you live in? This is not true in the US.

      • 0 avatar
        CoreyDL

        Probably England. They have on/off switches on all their outlets as well! (A good idea, so you can switch things off at the plug without unplugging if you desire.)

        • 0 avatar
          Jack Denver

          They also have fuses inside their plugs. Both unnecessary.

          • 0 avatar
            CoreyDL

            Well we do that in a way, with the breakers on GFCI outlets.

          • 0 avatar
            SP

            British house wiring (“ring mains”) is very different from US standard. From what I know, they have one or two circuits that cover the whole house. Because so many outlets are connected to the same circuit, the fuse at the box is something like 30A. And also consider that this is 240V single-phase AC.

            So, any appliance that has a short can instantly become a 7.2 kilowatt room heater.

            Now does the fuse at the outlet make sense?

  • avatar
    PandaBear

    Typical German Engineering blame everyone but themselves for not designing something with safety margin.

    Yes, every car should be in perfect condition and serviced perfectly, or your fault. Explosive on a battery cable that could trigger an airbag deployment. Wow, I’m speechless.

    I’d stick with American, Japanese, Korean from now on.

  • avatar
    panzerfaust

    “The more complicated the plumbing, the easier it is to plug up the drain.”
    Montgomery Scott, Chief Engineer USS Enterprise,

  • avatar
    andyinatl

    So, after reading the article and all the comments, I’m thinking that if this was Toyota/Honda/GM/Ford/ETC, NHTSA would’ve been all over them, pushing for a recall. Germans can just claim ignorance and say it’s a feature that is designed to protect first responders, etc? The fact is, the airbags deployed when there was no wreck. That’s a problem that needs to be addressed via recall.

  • avatar
    Slow_Joe_Crow

    Isn’t this one of those BMWs where you have to go into the dealer and have the battery “blessed” by diagnostic tool?
    I’m so glad the only BMW I deal with is a 1970’s motorcycle, whose only electronics are aftermarket parts.

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