By on July 9, 2009

TTAC commentator Derek writes:

My wife and I purchased a low mileage (50k, now at 70k) 2002 Dodge Grand Caravan two years ago when our fourth came along. We understand that the Siennyssey twins boast better build quality, but we didn’t have to finance the Dodge. Plus, we figured that Dodge had been building the Caravan long enough that they had worked out most of the larger Q/A issues. So far that appears to be true. However, there is one issue we’ve witnessed that I don’t understand. Every now and then (once a month or so) all power will momentarily cut off while the engine is running.

Usually, this will happen as I’m backing out of the drive. In that situation, the power steering will cut out for a few seconds and then kick back on—not a big deal. On the other hand, about a year ago we were headed east on I-90 around dusk. We were traveling at 70 mph with the van set on cruise, when the cruise cut off, the headlights when out, and the dash went blank. Disconcerting. I remember about a year ago (before the Piston Slap series) there being a post on TTAC where folks were discussing the large demands on electrical system in modern vehicles. And how the increased demand has led to some failure. Is that what is happening  here?

The battery is no longer the original, but I’m guessing the alternator is. Any ideas of what could be causing the problem?

Sajeev answers:

I see three areas of concern: the ignition switch is losing its marbles, a major component in the charging system is taking a dump, or battery cables are slipping off the battery terminals. Or perhaps the cables are attached so tightly they cracked the terminal inside the battery: that’s always a fun one.

As per usual, the Best and Brightest are right: modern cars have high electrical demands. And today’s multiplexed wiring harnesses mean that a weak battery or dying alternator causes spastic behavior that makes you think your vehicle is possessed. Luckily, parts stores test entire charging systems with a tool they roll out to the parking lot: no greasemonkeying needed. The test is accurate and 100 percent free.  Give it a shot.

Bonus! A Piston Slap Nugget of Wisdom:

If the alternator is bad, don’t buy a lifetime warranty unit from a parts store. Do anything to get a NEW (not remanufactured) alternator. While I’ve heard lifetime warranty alternators finally changed their evil ways, I’ve dealt with units that failed after six months of use. And left me stranded in not-so-happy places. Consider me scarred me for life.

On the plus side, now I can change my alternator in my sleep, so going back for a new one during an oil change isn’t a big deal. Not that I would . . . but I could.

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27 Comments on “Piston Slap: Getting a Charge from Your Caravan. Or Not....”

  • avatar
    Steven Lang

    The power steering issue he mentioned is actually common for Chrysler minivans. He should expect some leakage in the next year or two. Replace the hoses and all is fine. IF not, replace the pump. If you ignore the new whining sound, you may very well have the steering rack to deal with.

    Ignition switches are not a big issue in these vehicles. However Sajeev’s recommendation on a free alternator test is spot on. I would be very inclined to think that the alternator is gradually losing it’s strength.

    A lifetime warranty one would not be a bad idea. NAPA tends to offer very strong alternators. Autozone and Advance, not so much. You can also get an OEM one from the junkyard for real cheap, which is what I usually do when faced with this scenario.

  • avatar
    Gardiner Westbound

    That has to be setting a fault code. Try an OBD scan tool first. Many parts stores, as the author pints out, will do it for nothing.

  • avatar

    I have a 2000 Neon, and once or twice i have noticed the power steering getting stiff as if the engine died when it didn’t. the failure would happened for a split second mid hairpin.
    I didn’t notice the whole car fail electrical because it was daylight in both occasions.

    i never actually thought about it because it hasn’t occurred for a couple of years, but now that i do think about it, and hear someone else had a slightly similar problem it’s concerning.

    other than that, i never had a problem before, and i always thought it might have been a slip from the belt that runs the hydraulic steering pump when at or close to full lock.

    might Derek’s issue happen if the Belt slips on the alternator. plus having a dying alternator might induce an electrical balckout. but why would the power steering die, the Dodge caravan runs on a belt driven hydraulic power steering pump not electrical. so it might be the belt (pulley) that lays on the main shaft and drives the belts…

    I’m not a mechanic, I’m just guessing…. hope it helps…

  • avatar

    This is a tough one. If it’s a battery cable that is loose the alternator should cover the need and it the alternator has a problem, momentarily, the battery should cover.

    I believe there is a “power distribution block” (not the official name) under the hood that routes all things electronic and contains circuit breakers; the problem is probably there, either coming in, going out or internally.

    A fully electronic test may help but being that it is an intermittent problem, it may be tough to diagnose. Sounds like a momentary “dead-short” if it is taking out everything at once.

    MOPAR mini-vans have some specific “recurring” issues but I have never heard of one like this.

  • avatar
    montgomery burns

    Back in my mechanic days we would get something like this from time to time and if it wasn’t a common problem was difficult to track down.

    If you are getting a failure just backing out of the garage or in similar circumstances i would not say that this is a load problem, sounds more like a vibration/flexing problem. If every system in the car goes dead, it’s going to be something very basic. Since most cars have the “whole world grounded to one bolt” system, that would be a place to look. Also as Sajeeve mentioned could be cracked battery terminal. Bad positive connection at either end or bad cables. We many times replaced cables that looked good from the outside but were completely corroded inside.

    Part of figuring this out is to determine if the whole car is dead or if just the primary systems go dead. Difficult with an intermittent problem, I know. If just the primary systems go out, it could be a bad connection to the fuse box, a common problem on 90’s Saturns for instance that would kill almost everything but some things like the radio still worked.

    Good luck with this.

  • avatar
    John Horner

    Good luck. We had a Chrysler Town & Country bought back by the company under the lemon law because they could never fix the intermittent failure of the dash lights. Chrysler’s electrics make Lord Lucas proud.

    On ours the dealer replaced the “body control computer”, instrument panel and other stuff and never found whatever was intermittent.

  • avatar

    Gardiner Westbound : That has to be setting a fault code. Try an OBD scan tool first. Many parts stores, as the author pints out, will do it for nothing.

    Since the engine is running when these problems happen, there’s a good chance no OBD codes will pop up. Which has been my experience too.

  • avatar
    Daniel J. Stern

    Do anything to get a NEW (not remanufactured) alternator

    This advice is poor, because it is misleading by dint of vagueness. “Factory remanufactured” parts widely available from parts stores are usually poor-quality, unreliable trash, but the “100% NEW!” rotating electrics (starters, alternators, etc.) available from many parts stores are counterfeit/copycat garbage from China with awful durability and reliability, no better—regardless of whose name is on the box—than the “remanufactured” junk. Both the “100% NEW!” and the “reman” items are often promoted with a lifetime warranty. This means nothing more than that you’re dooming yourself to spending your lifetime swapping repeatedly-failed parts under warranty.

    The good options are a new original-equipment item from the dealer ($$$), a tested-good original-equipment item from the wrecking yard, or one—the car’s original or another—that has been rebuilt on a workbench by a skilled technician. The latter two options are much more cost-effective than the first. Warranty? Yeah, maybe 30 days or a year. In over two decades of preferring carefully-selected used or bench-rebuilt components to factory-“remanufactured” ones, I have never once needed to make use of the warranty, during or after its effective period.

    You have to use your brain, though; there’s a great deal of slop and overlap in usage of the terms “remanufactured” and “rebuilt”.

    Other potential causes of the subject vehicle’s symptoms include internally-corroded or -broken battery cables that lose continuity when they flex a certain way, a dirty or loose main disconnect located on Chrysler products in the positive battery cable about 6″ away from the battery, faulty power or ground to the ECM and/or BCM, or (occasionally) a faulty ECM or BCM.

  • avatar

    Since the problem manifests through the power steering and electrical system and the only thing the two systems have in common on this vehicle is a drive belt, the question that bears asking is if it could be as simple as a problem with the drive belt? Could it be a slipping or bad belt, or a belt tensioner that is hanging up allowing the belt to get loose at times and slip, producing low voltage or causing the PS pressure to drop momentarily?

  • avatar
    John Holt

    Frank Williams +1 … assuming the two are related. Otherwise they’re likely seperate issues.

  • avatar

    Steven Lang,

    Just curious, but if power steering hoses and pump aren’t replaced what will be the resulting failure mode of the rack & pinion?

  • avatar

    Frank Williams +2, assuming you lose power steering every time you have an electrical problem.

    If that’s not the case, I’d certainly check for codes and have a charging system test (since they are easy and free and sometimes point you in the right direction), but I’ve had a bad ground before that behaved similarly (but never affected power steering…that’s the curious part), so I’d also second the commentator who mentioned that…

    Intermittent problems are a bitch, though. Sometimes you just replace things as best practices dictates (and budget will allow) and see if it goes away.

  • avatar


    If you’re serious about finding out what it could be before you take it somehwere for service, check the forums at Those boards are frequented by technicians and Moparites of many years experience. They will point you in the right direction. You have to register to use the forums, but it’s free and they won’t give away your email address so you suddenly start getting SPAM for male enhancement products.

    To register:

    Then go to:
    “General Technical Support & Help”

    Or go to:
    “Minivans – Pacifica”

  • avatar
    Paul Niedermeyer

    Total brief intermittent electrical loss like this is not going to come from either the battery or the alternator, since either one cover for the other.

    rpol35’s answer is almost certainly the right track: a power block or some other major electrical junction/distribution point is having an intermittent failure. The power steering issue is is a separate problem. Good luck; you’re going to need it.

  • avatar

    Hey, it’s a Chrysler product, it’s SUPPOSED to have electrical problems!


  • avatar

    From my experience, the same thing used to happen on my 1982 celebrity and when we changed the computer the problem was gone. (i was stalling sometime when in reverse). (my Dad was a GM mechanic so…) hope it works for you!

  • avatar

    It will likely be battery cables or connections. Most alternators cannot keep up 12V when not connected to a battery. You likely lost power steering because the engine died for a second, because of no fuel or spark.

    If it was the alternator, your car would run off of the battery until it discharged to much, than the car wouldn’t run at all.

    On a side note, the issue with the rebuilt alternators is that they don’t change the voltage regulators if they pass their test. I had one go about 30 seconds after putting it in and staring the car. Just pay attention to the battery light. If it comes on don’t turn of your car if you don’t have to, use the minimum amount of accessories.

    My father had a Lincoln Continental that I borrowed a couple years ago. I was sitting in a McDonalds parking lot listening to the radio. I started the car, pulled out onto the road, and about 50ft later it died from a bad alternator. Luckily their was an Autozone across the street. I didn’t have the time to change out the alternator though because I had to go to a college final. I bought a battery and jumper cables. I placed the battery in the foot well, ran the cables out to the hood through the window, and was able to get to class, and home like this. Obviously, radio, lights, everything off.

  • avatar

    My 1998 Voyager had both problems.
    The P/S issue is most likely a pump getting ready to fail. Typically, the pump input shaft will snap in two but the belt will hold the pulley in alignment. The pump will appear OK, but won’t provide any assist.

    The electrical issue was caused by a wire behind and above the LF inner fender. The insulation was cracked, allowing the wire to short-cicuit.

  • avatar

    There is a recall on both power steering hoses on 2002 Caravans, at least in Canada. I think the op code is D-18. We did hundreds of them.

    These are good cars for the money but a 2002 is going to start to cost money at that age and mileage. I used to tell people to trade them at 130,000 km or approximately 80,000 miles. At this point it will be one thing after another, especially transmissions.

  • avatar

    I would check the fuse to see if it covers the three areas that went black at the same time. Sometimes the simplest and cheapest fix is the right fix.

    On the other hand, I think this is the kind of thing that owners of middle-aged Detroit iron just kind of get used too. This from the not-so-proud owner of a 99 Grand Caravan ith 116K on the odometer.

  • avatar

    coworker had a simlar issue with their 99 neon about 3 months after a minor front end crash, independent repair shop chased the problem for a week, they actually drove the car to lunch, etc for a bit trying to duplicate the issue..finally found a molex type connector to the onboard computer that had a loose tab on it… reseated the plug and bound it tight with zip ties and never saw that issue again..

  • avatar

    about a year ago we were headed east on I-90 around dusk. We were traveling at 70 mph with the van set on cruise, when the cruise cut off, the headlights when out, and the dash went blank.

    I had the same exact thing happen to me on the freeway while driving a rental GC a few years ago, so I’m guessing we’re not the only ones. I’d check Dodge message boards to see if it ever got figured out.

  • avatar

    The last alternator I bought had a lifetime warranty. It was a brand new Hitachi. It’s only been in the car for four or five years, but no problems yet.

  • avatar

    If all those systems go out all together, it has to be part of the main power distribution. Chryslers used to use a ASD relay that would kill everything if it failed. As others have posted, an good alternator would carry the car with a bad battery and vice versa. Since the engine continued to run, the circuits that power the fuel pump, ECU, etc must have still have had power. You will need to check the wiring diagrams and see what circuits the affected accessories have in common and check there. Common ground points need to be checked for corrosion or damage; green/white corrosion or melted connectors are a sure sign of high resistance. This type of problem will take perseverance to fix, plus good wiring diagrams. I really don’t think the alternator or battery themselves are to blame, but both of those items are easily tested.

  • avatar

    Try replacing the battery. On my wife’s 2002 Grand Cherokee the odometer used to flash ramdomly, 5 to 10 times every 4 or 5 weeks. I replaced the battery and the odometer did not flash in 2 years.

  • avatar

    I did speculate that it would be belt related, and Frank Williams nailed it. i completely forgot that the Dodge would have a single belt snaking around the engine. which makes the culprit even more obvious.

    since the power steering is failing as well i would eliminate battery terminal crack, power steering hoses, or alternator mafunction unless the alt is jamming and holding the belt up in some way.

    i still think as Frank said it would be a belt tensioner or the main drive pulley on the crank slipping or something… it sounds logical and worth a check

  • avatar

    My father always said mopars suffer complete electrical system failures, at least the Germans didn’t engineer that feature out.

    YOu can try a wiggle test under the dash and through connectors at the firewall. With the key on have someone watch the dash and see if it shows.

    Clean connectors with contact cleaner spray, especially where they go under the dash through the firewall.

    Power steering is a 1000 dollar repair on the road, trans is 4000 dollars. Keep a credit card with big limits handy.

    My mom lost her tranny at 25k, AC at 38K, and power steering at 40K. The last one was a 1000 dollar repair for the pump and rack since when the fluid ran out of the bad rack it destroyed the pump.

    These vehicles are not highly rated for longevity.

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