While hard wiring my GPS I removed the access panel on the drivers side. I found what appears to be a relay. There is a connector that is not connected to anything. Any clues

 

Another Pic

 

Hmmm...did you get your HHR used?

The non-GM spade terminals, inline fuse holder, and relay all suggest someone was there before you hooking something up that's now gone. Foglights, stereo, security system, hard to tell.

 

My bet would be a security system and/or remote start. But, if that bit at the top is a piezo noise maker then I'd say stereo system.

 

I bought the car used, it's a 2006 with factory stereo.

 

That does not mean the previous owner did not have a special stereo system and saved the factory unit for resale. Does it have remote start?

 

In my other HHR I had a stereo with DVD player and I had to hook up a relay to ground to allow DVD to play without parking brake on. I put factory stereo back in when I traded it.

 

Yes it does have remote start, (from factory).

 

might be for serius radio?