Yesterday as I was stopping at a stop light the "charge" and "brake" lights came on at the same time on my '88 Vrunner (V6 engine). I also noted that the voltage level was not as high as usual, so it did appear that the alternator was either supplying no power or minimal power. I pullled over and looked around, only thing unusual i noted that the wire bundle near the alternator was touching the hot metal that covers the exhaust manifold. I moved it out of the way a bit. Then after driving another 1 minute, the warning lights went off and voltage went up to normal.
I've driven about 30 miles since then and no problems. I adjusted the wiring so that it will no longer contact the hot metal.
I'm concerned that this will happen again, and next time the problem may not go away. It's possible it was caused by the wires getting too hot, in which case my adjustment will prevent it from happening again, assuming there was no permanent damage. but i suspect it's more likely my alternator is just getting old, it's the original. My '88 V6 has about 235,000 miles on it. Never had any major problems.
Any thoughts? Why did the brake warning light come on also? Was the system voltage level too low such that the brake fluid sensor thought it was getting a fault signal? Or, is it because the brake fluid sensor wire goes through the same bundle of wires, and it got shorted to the alternator power wire????
Thanks, Paul