I don't know what is goin on here, hopefuly someone here can help me out.
The car acts fine for about 3-4 weeks then out of the blue it won't start, i mean no radio, no lights, nothing but the security light.
Then if you disconect the batt. and then hook it back up everything is back to normal, any ideas?
The shop i took it to thought it might bethat the cluster is bad, but i have no clue.

 

The security light is the key. When that comes on it means that the security feature is failing and therefore nothing will work. If you have an aftermarket alarm or remote start system then it could be a cord being unplugged or a bad bypass box.

If you have a stock system, then the key cylinder is probably the cause of the problem so you would need to replace that. The reason that the 20 min is clearing it is because it is clearing the ECM info.

 

Oh, i forgot to mention it does not have a aftermarket alarm, and the key cylinder has already been replaced and it still doesn't start now and then.

 

could possibly bea battery on the way out, when the car is shut off whats the voltage on the battery?

 

Man im really dropping the ball, i also didn't mention that i put a new batt. in to.
Is there a chance the key is messing up? I only have one, do i need to get another one and go from there or...? I really don't know. The only other thing i didn't say is that the locks aren't working, it has a bad drivers side switch.

 

Wow. That's getting messed up Eric. What year Monte do you have?

It's possible to be a defective new battery and it's also"possible" the switch is causing problems.

The key can wear out it time and you may need to replace it. Since these keys are pretty special now you are looking in the $50-$70 range.

Here is a great beginners article on the GM Security system and how the VATS and Passlock systems work.

http://www.search-autoparts.com/sear...09/article.pdf