Three relatives nearby and another relative living a thousand miles away had car faults within the last year. The most obvious one was an intermittent ignition fault. The most puzzling one was the total failure of the ABS. This we traced to a lack of feedback from the wheel speed sensor. All four were due to the same basic fault.
Was it corroded battery terminals? Its amazing the wide array of seemingly random and intermitant problems that can be caused in a modern (computer controlled) car when the various sensors arent getting a consistant and adequate voltage.
The problem in each of the recent problems was a rodent eating the wire insulation. This problem has existed for many years. In past, it has been rodents gathering nesting material or it appears sharpening their teeth. But it may have become more common due to substituting soy oil-based plastics for the previous petroleum-based plastic insulation. Checking under the hood for nesting material and removing it is a big help, and coating the wires with powerful pepper oil and then covering with plastic tubing has also worked
I've had mice destroy more than one heater fan... havnt had them chew wiring though. But your theory about plant based wiring insulation sounds plausible. On asimilar note, my house was built in 1942 and it still has some of the original wiring. One time while assessing a plumbing issue in the crawlspace, I noticed a large (thankfully abandonned) wasp nest in one corner of the crawlspace.Then I noticed that next to it was about 4 feet of entirely exposed two-lead residential wiring, and it was live. Miraculously the wasps had managed to chew all the tar-fabric (or whatever the hell it is they insulated wiring with back in the 40s) without the two copper wires inside ever touching. Obviously I've fixed it, but I wonder how long it was that I was blissfully unaware of being about 1/8" away from an electrical fire because of those damn wasps... I also recall someone telling me about an older experiment with 'biodegradeable' wire insulation being used on some model of car decades ago. After around 20 years, they tended to catch fire. I dont remember anything more specific than that except its why they don't (or werent...) doing that anymore.
Several times now people have asked me what I think is wrong with their car, and I told them 'check the battery terminals'. They didn't, the problem continued until they finally got me to look at it myself and SURPRISE it was the battery terminals. This usually after they replaced some other, often expensive, part... And yes, I did the same thing to myself quite recently. I replaced my starter solenoid (thankfully a pretty cheap part) only to find out that the positive battery wire was corroded and loose inside the terminal block (I did clean and check the terminals, just not very thoroughly)... but hey, now I have a spare solenoid, at least.
