I received one keyfob from the previous owner and wanted a second for my wife. Not wanting to spend $150 for one from the dealer, I bought these from Amazon

As it turns out, the only thing that works on this remote is the panic alarm.

The dealer told me that the aftermarket key fobs are rather hit or miss. If anyone has had success with Amazon or Ebay aftermarket fobs, if you can link which ones you bought this may be a useful reference thread.

 

Used to be on eBay the Genuine GM fobs were not much more that the junk.
This is a random one, Sort of suspicious, it has a blank back. NEW 2006 2007 2008 2009 2010 2011 CHEVROLET HHR REMOTE START KEY FOB 15114374 | eBay
If you were trying to use it for your Panel there is a good chance the dealer didn't know how to do it.
Amazon will replace or refund with no hassle. Might even be the wrong PCB in it; the Panel should have 6 buttons, Remote start At the least.
The rule of thumb is "if it has an LED on the PCB it won't work right".

 

That part number fob won’t work for a panel , no buttons for the rear door popper

Yours should have 6 buttons , similar to this
s

 

Yep, what he said.......

 

Strange thing is, it has door popper buttons, but no remote start

 

Then you got the wrong fob or possibly your hhr doesn’t have rvs

 

That's a fob for a panel HHR with 5 speed trans. No remote start with a standard shift.

 

AND, remote start is "Lock then Panic+Lock". All Automatic trans HHR have RVS.
One of the faults with the after market fobs is the combination keys don't always work. RVS, resetting TPM positions etc.

 

Sorry Donbrew but not all automatic HHR’s have RVS , my 2011 doesn’t have the hood closed switch, and your button sequence doesn’t work.

 

Forgot it was optional delete on former fleet and optional on 2011. Only 2008 former fleet without can be diddled with to work.
But, if you look at the PCB of a genuine fob you can see the traces for the buttons; lock and panic both combine at the RVS pad.