Prompted by the thread on Cougar’s brake light fuse problem, I recall two incidents and pose a query.
First, in Spring 1962 my Dad got a new Plymouth Valiant (slant six; manual transmission, the one where the forks on the linkage would jam from time to time). A few days later the friend following me complained about my driving – “signal right, turn left; and vice versa.” Turns out the rear turn signals were cross-wired.
Second, a few months ago I was following a new small Chevy (I don’t remember the model, but I think it was near the bottom of the line). Every time we neared a stop light his brake lights went off. As we started up, they would come back on. After a couple of cycles, I deduced that they were in reverse-logic. At they next stop I jumped out to tell him. “I know, $*$&^!!” he growled. (“So why don’t you get it fixed,” I wondered, but did NOT say.)
Query: On a '62 Valiant I guess a lot of connections were quick-disconnect types; easy to mis-wire right and left, or normally-open and normally-closed. But it seems that on modern cars everything has a keyed connector plug/socket, and I’d presume that the harnesses are checked at manufacture. So, even if the brake light switch did have a normally-closed contact, how does it get mis-wired? Or is there some other explanation?