I own a 2008 HHR, I am having a problem that I hope someone can please help me with. I installed an aftermarket stereo in it about 3 weeks ago, alone with the required interface, and everything was working fine. then a couple of nights ago I turned the ignition key off and pulled the key out but the engine was still running. Then when I opened the drivers door the engine shut off. Now it does this every time. The radio and power windows work when I turn the ignition off for about 10 minutes or until one of the doors is opened. I have tried turning the stereo off after I turn the key off but the engine continues to run. I am a fairly good mechanic, I am 63 years old and have been working on motorcycles, cars and almost anything else mechanical. I I am stumped, and not sure what steps to do next to diagnose this problem. Please help.

 

You probably wired the accessory voltage wrong.
What interface did you use? What did you use for switched power?
Sounds like somehow you got the ignition wired into the RetainedAccessoryPower system.

 

I’m thinking the adapters aren’t correctly wired. As Donbrew points out the RAP is not wired correctly