Questions and Answers
Lights On... Lights Off
Q. I've got a 1985 Toyota truck, 2-wheel, automatic transmission, no a/c, no cruise control, with a carb. This past weekend, the charge light and the brake light came on when I started it. When I put it in drive and accelerate, these lights go off. When I stop or slow down, they come back on. What could be the problem?
Thanks for your help.
ChadA. Chad, this is a classic symptom of a bad diode pack in your alternator. The diodes turn the AC current produced by the alternator into DC current that your car uses. They also are used to turn the dash charge light on when the alternator is not charging. Now that's not to say your alternator is not charging, just one or two of the diodes are bad. You'll have to replace the alternator to fix this problem.
I would check to make sure your idle speed is set correctly and the alternator belt is in good shape and at the proper tension. These two simple things could also cause the symptoms you are experiencing.

