Ok driving down the highway yesterday on the way home and all of the sudden all three lights came on at once. A/T oil temp light, charge and brake light. Why are they all on at the same time? I can understand the charge and brake light but throw in the A/T light too????? I drove it this morning and it had sat all night so I know the tranny wasnt heating up but the light is still on. Anyone have any suggestions on where to start with all three being on?

 

I would check the charging system. I've seen low system voltage turn on multiple lights before. It's a place to start.

 

Alternator.

 

Ok short of taking the alternator off and having it tested. I will throw this problem in too. The truck runs like crap after all the lights went on. It has no power and the tranny shifts like crap. Auto tranny. Could an alternator throw everything off to the computer and screw this all up? I guess I will take off the alternator and have it tested.

 

x2......

 

bad alt or associated wiring

think about it. if your alternator isn't charging your battery, how are your spark plugs going to fire once the batt drains down?

 

Thanks guys for all the replies......Took alt off and had it tested. Failed all tests by two differant places. Installed new and back to normal again. No lights!!!!
Thanks everyone!!!!!!