A number of articles have appeared implicating tin whiskers as a potential source or complicating factor in Toyota’s (and other manufacturers’) unintended acceleration issues. The phenomenon of tin whiskers, a crystalline metallurgical phenomenon involving the spontaneous growth of tiny, filiform hairs from a metallic surface, can cause short circuits and arcing in electric equipment. First discovered in phone switching equipment in the 1940’s, the addition of lead to tin solder largely eliminated the problem. But the push to eliminate lead from electronic assemblies has led to a nasty re-growth of the pesky whiskers. And some are pointing fingers.
Satellites, including the failure of Galaxy IV, nuclear power facilities,pacemakers, and numerous other electronic assemblies have suffered from the effects of tin whiskering (here’s an explanation). In an article at TechEYE.net, a document that details the issues with lead-free soldering is referred to. Another expert in the field Henning Leidecker, chief engineer of the electronic parts office of NASA’s Goddard Space Flight Center in Greenbelt, Md., and an expert on tin whiskers, said in the last four years his office has been contacted by seven major suppliers of automotive electronics inquiring about failures in their products caused by tin whiskers.