Tin Whiskers

Electronics are often built using lead, which raises concerns from good meaning people who are worried about environmental damage or the contaimination of children. These are honest enough things to be worried about, and so there was a push starting in the 1980s to switch electronics over to lead-free construction (meaning lead free solder, led free components etc.).

Did you know that lead-free electronics are explicitly banned by the defense, medical, and aerospace industries?

That's because the alternative to lead in electronics uses various tin alloys. As time goes on the metal alloy degrades and distorts. The exact processes involved here is still a mystery to chemists & physcists, so I do not have a full explaination for you.

But I can tell you what happens.

The lead substitute grows metallic hairs (known as "whiskers"). When you have electronics tightly backed together as found on many printed circuit boards this is a serious problem that hampers safety & reliability. The whiskers, being metalic, conduct electricity.

Guess what happens then when those hairs start touching something else that's near by on the board?

You get a dead short and things stop working (if you're lucky) or go up in flames (if you're very unlucky).

Lead, like asbestoes, is a miracle resource when used & disposed of properly.

Many automotive computers suffer from the solder joints on board components failing. No one brand is more guilty of this defect than others (just google: volvo abs tracs computer failure for a prominent example). Boards can be rebuilt to some extent, but not if they use proprietary chips that are not avaible on the modern electronics market, or closed-source software that is not being distributed by the auto maker.

John Deere has gone so far as to sue anyone who tries to work on their tractors' computer systems under IP law, claiming they own the software and do not give the public a license to troubleshoot it (seriously).

So you can clean up tin whiskers and reflow solder if a solder joint gets compromed. But much more than that gets dicey.