I have a 99 Montana, I’ve been having problems for some time, It started out with the anti lock brake lights on inside the dash, I could back the car out of the garage, shut the car off, restart the car and put it in gear and the light would stay off till the next day, sometimes sooner. And the blinkers would blink real fast when I stepped on the breaks, been doing that a few months, and now the anti lock break lights are out but the blinker lights are both on solid at least most of the time, the blinker lights on the outside are real dim and blink faster than normal. I also have no brake lights. The radio display light will also blink real fast too.The head lights have a lot of water in them , like lots of humidity, aren’t they suppose to be sealed? Could they be shorting something out? I have the mechanics stumped. Got to get this fixed can you help me out.? Gramma in Nebraska
There may be a grounding problem causing the trouble. I would clean the battery connections and the bond to the chassis to see if that will help. Also check the flasher unit for a problem.
Here is another thought that just came to mind. See if the lights stop flashing while the ignition is ON but the engine isn’t running. If that is so then have the charging system checked for AC voltage across the battery. The alternator may be bad.