I have a 2009 2.4 HHR. I have it set it up to pull behind an RV. I am a pretty good mechanic, but I am the worst person in the world to work on electrical problems. I spent almost $3000 dollars on computers, dealership visits and stuff that I have done by instructions from other HHR members. Where I am at on this is I want to drop it off and pick up. Hand you your money and brag about you on the web sites. I can tow this car so traveling is not out of the question. So can anyone help me? Thanks in advance. PM Oscar or respond on this site. Thanks for any help! 05/20/2024

 

Nobody here suggested computers.
Is this about the AC problem?
Have you looked at the pressure switch?
Do you have a P0128 code in history or pending ?
Have tried an AC shop?
The ground for the relay comes from the ECM. Based on input from the ECT, the Pressure switch, the blower switch and the AC button.

 

so….what is the issue with your car exactly?

 

a/c?

 

Perhaps an explanation of the issues you’re having.
Any CEL codes? You mentioned electronics, have tightened up the 4 bolts in the under hood fuse box? Are all the fuses and relays firmly pushed into place?

 

Started with A/C problems. The only way to get it to work is jump the relay. Have changed out both computers and reprogrammed by the dealership. On the a/c changed compressor, pressure switch, thermostat, temperature sensor,relay and climate control on console. The only thing that I see wrong that has changed is my radiator fan used to run all the time and by all the time I mean when you crank the car it started an ran until 4 minutes after you turned the key off. Now it takes for ever to get the fan running even with the a/c compressor jumped and running. Someone mentioned clean the grounds. I disconnected the battery cleaned the grounds, hooked up the battery and now the security system has me locked out.I seem to only be making things worst, that is why I would like to find someone that knows these cars, it is defiantly not the dealer here, I bring it to them and the charge me a $1000 dollars each time and let me know that I still don't have a/c.

 

Yes I have tightened the bolts and pushed all the relays and checked all the fuses.

 

Then you need to take it to a reputable AC shop.

 

Whoever suggested computers is an idiot.
Somebody messed the cooling fan up.
My bet is the wire from the blower switch to the BCM that tells the AC it is on is broke/burned/not connected. Maybe the wire/connection from the ECM to the fuse box.
Why is the AC this important for a toad? Why not spend your money on an AC shop instead of internet mechanics. GM dealers do not know anything about 15 year old cars, the book says "replace the computer" so they do and charge you for non-refundable parts.
What about OBD2 codes? Your local parts store will check for free; get the numbers and type (historic, permanent, current, etc) only. If P0128 appears anywhere change the t-stat with a ACDelco 131-158 ONLY, maybe do that anyway.
Does the digital coolant temp readout work? How long does it take for the temp to rise tp 180F from a cold start?

Either the wire is bad or there is something inhibiting the AC on signal.