I have an 04 Monte Carlo with heater issues. Stopped working and replaces resistor. Seemed to fix the problem for about 1 month. Now it is working only sometimes.It seems lots of things are going on at one time. Speedometor will suddenly stop working the start again, same with tach.Begining to think it is haunted lol Any suggestions?

 

It kind of sounds like an issue with your ignition cylinder, a few members have had problems with the accessories, when the ignition was replaced it solved there problems, so just a thought.

 

Thanks ! I will check into that

 

Actually, I would consider the ignition SWITCH first, then the cylinder if that doesn't fix things. It's the most likely culprit, is cheaper and you don't have the issue of getting a new ignition cylinder re-keyed. I had the same issues as you and more: abs light, brake light, security, airbag etc. all wigging out. Bought just the switch for about $40 and all problems were completely fixed.

 

Thanks for correcting me I was thinking about the switch but said cylinder.