Although this doesn't ALWAYS happen, it seems to be getting more and more common...from the time when I first turn the car on to the time I turn it off (or even if the key is just in the "Run" position but the engine is off), my ABS and Parking brake lights will flash randomly and if I try to roll the windows down, the ABS light will stay on as long as I hold the switch down. My HVAC doesn't work either. (It used to work while this was going on, but more recently began to fail along with the window motors) I'm not sure whether or not the compressor kicks on, but the blower motor definitely doesn't work...If I pull over and turn the car off then back on, it will sometimes do the trick. Could this be the ignition switch acting up? Would replacement be the only option and how time consuming is this job?

Thanks,
Jacob

 

Sounds like you've got a grounding problem. The power circuits for these systems is not shared. Due to the fact that the windows affect the ABS system, I'm thinking you've got a ground somewhere that has corroded or otherwise lost continuity with the chassis ground loop. There are a few grounds on the firewall under the dash that could affect this.

Have you ever had a water leak at the windshield or had the windshield replaced? Or have you done any wiring modifications under the dash?

 

The windshield has never been replaced and the only wiring mod I have done was for the headunit. If it were to be a ground, how would fiddling around with the ignition cure the problem? When my heater core went for the second time I had quite a little puddle in my foot wells...I'm assuming no grounds would have been down there but...? Anywho thanks much for the help!

 

Grounding problems manifest themselves in VERY confusing ways. The fact that so many systems are affected leads me to think it could be a grounding problem.

But I do suppose that it could be ignition switch related. These trucks are known for ignition switch failures.

Without being there, it is very difficult to recommend a course of action with this type of problem.

 

The cheapest thing to check out first, is your grounds... That's free to fix, unless you've gotta replace wires... Which is cheap, lol.

Off the top of my head, I can't remember where the chassis grounds are, but the battery ground is easy enough to check, lol.

 

Still haven't got it fixed. Just another note to add...if either one of these works when I first start the car in the morning, then it will work for the rest of that day...maybe it somehow has something to do with engine temperature. Same goes for if they don't work.

So basically if when I first go to my car in the morning and try to roll the windows down and they work, I know it'll be a good day.

 

All my problems were caused by the Ignition Starter Switch. Thanks for the help guys!