Chevy HHR head unit problems! please help

I have a 06 Chevy HHR. Have several problems with this car. This is the current one. The battery died from the ignition switch being left on. I had it jumped off and this crazy anti theft System finally let it crank… the radio, blinker sounds, and warning sounds no longer work. What could cause this? What could i do to try and fix it?

Most of the time I prefer to use a memory saver, but I think in your case buy a new battery, let the system reset and go on from there.

The battery works fine. Holds a charge well. The radio just won’t light up or anything. How would i go about resetting the system?

Does the radio display LOCK or LOCKED?


Its completely black. Won’t do anything.

Check the fuse for the radio to see if it’s blown.


When you jumped the car…could someone have hooked up the cables in reverse.


Anything is possible. There was a lot of messing around with the battery, but I’m extremely careful not to do that and the only other guy messing with it is a mechanic. I’m really hoping that it’s not the head unit itself.

I’m not sure what you mean by “Head unit” Computer???

Cylinder heads… totaly unrelated to this problem.

And “holds a charge well” means nothing unless you have the testing equiptment to check it…and not just a volt meter or turning on the lights.

First I’d agred with @Tester; and check all those fuses. You could also have blown a fusable link.


The “head unit” is the audio unit.
I thought of the security code that they all have not that’s required to “reinitialize” the head units, but since you have other stuff out too, I’d start by checking the respective fuses. Or just changing them. Fuses are dirt cheap. The owners’ manual will tell you which ones are appropriate for the audio system and for the blinkers.

I believe the head unit is the same as the one in my 2010 Cobalt. The blinker, warning chimes, etc all come through the head unit and out the left speaker. No head unit, no sounds. I found out the hard way when the left speaker failed. I would check the fuses first.

A replacement radio can be bought from Crutchfield, an adapter to enable the turn signal and warning chimes is available at additional cost.

Ed B.

Okay I’ll get to checking them as soon as i get back from being on the road. Thank you all. I’ll update soon

Thanks TSM, I never heard it called that. Always learning!!!


I’ve learned something too. I was totally unaware that on that car the chimes etc. were sent through the audio system to be pumped out the speakers. It’s always a good day to learn!

I had a stereo malfunction in my 2002 Mitsubishi Eclipse following a battery replacement. When I turned on the radio there was no sound. The display read “CODE”. It was the middle of December. Of course it was code! It suddenly dawned on me. The anti theft code was triggered by the battery removal.