I have a 2007 HHR and the climate controls stopped working. This happened once before maybe a year or so ago, but cleared up on its own in a few days. Now it is happening again. Here is a list of the symptoms:

• The temperature and mode selection dials stop working.
• The AC and Defrost buttons on the dials don’t work.
• The seat warmer buttons don’t work.
• The circulation buttons don’t work.
• The center fan speed control does work. The fan can be turned off and to the various speed settings.
• Heat stays on full heat (no matter what the temperature dial is set to ) directed to the dash vents.
• All fuses look good.

As I mentioned, it happened about a year ago, but “fixed itself” after a couple of days. This time it’s been about a week.
Any ideas of what to look for?
Thanks!
John

 

Sounds like loose or fried wires on the control module. Maybe a bad control module.
To remove the waterfall stick your fingers in the center AC outlets an give a sharp yank.

 

Thanks! I'll take a look there this afternoon.

 

Look for melted plastic in the connection on the back of the control module , see post #8

https://www.chevyhhr.net/forums/prob...control-63603/

 

Other obligations and weather have kept me from having time to pull the waterfall to take a look. But when I went to the grocery store this morning everything was working again.

I still plan to open it up and see what the connections look like.

John

 

Hmm, a loose ground wire or relay?

 

The car was parked for two days. The controls weren't working when I parked on Monday. They were working on Wednesday when I started it up. I had been driving around with it not working for the past 10 days. So it doesn't sound to me like something moving or getting jostled around.

 

Ok, but those 4 bolts loosen up over time, in our experience enough to cause problems.

 

Which four bolts.

Thanks!
John

 

Oldblue is referring to the bolts in the under hood fuse box. But, based on your description of your problem, I doubt it’s the fuse box.
Sounds more like it’s a bad or intermittent condition at the HVAC control panel. Either the switch assembly or wiring plug in at the switch. You should pull the waterfall as Donbrew suggested. Check for signs of arcing or brown burn marks.