Driving to work today my brake and charge light were flashing together very briefly and intermittently. It seemed like it occurred when I hit bumps in the road. I searched through the FSM and and couldn't find anything regarding both lights coming on at the same time. Obviously I know the problems from one or the other flashing, but has anyone else seen both flash like this? It didn't seem to do it once the engine was up to full operating temp either. Truck seems to be running fine otherwise. I will check charging voltage when I get home, but I suspect lose wire/fuse/ground???? Why both lights??

 

Charging voltage is normal. Thanks for the input guys.

 

Both lights indicate a charging warning, which means the alternator is probably on its way out. If they were flashing over a bump or something I would suspect a loose wire or ground..