After giving this more thought, I had referred to the item that might be causing your problem by the wrong name. I said 'cycle switch' which led us to 'pressure switch' and I even described it's location. What I was actually referring to is the evaporator temperature sensor not the pressure switch. It probes the evaporator temperature and prevents it from freezing by cycling the compressor. That is, if the HHR even has one. Many of the modern vehicles accomplish this function through the BCM.

@donbrew: You say "Mine does a good job and has a good pressure reading and never cycles on/off."

Generally this would happen on hotter days while driving and you'd never notice it when it's working properly.

 

YES,I understand. I used the term "pressure" 1st, but I recall now Auto Zone had 2 distinctly different switches. "Pressure" came to mind since they were getting bad "pressure readings"

But Temp makes sense.

Thanks for the explanation. I am saving your comments, and just hope it works ok this year.

I hope the orig poster is reading because I went thru $475 in diagnosis/rescharging, and this may end up being HIS problem too.

By the way, the dealer had one switch/sensor in stock, and Auto Zone had 2 different ones in stock....

 

This old picture shows a switch on the compressor.
(the red circle was for another thread about Tmap wiring)

 

WOW! Awesome FiremanGeorge! you got a good memory to find that!!

My favorite Uncle was George and a Fireman in Phila!

Thanks!!

 

My HHR LS 2007 air condition fan only works on the high blower and it make lots of noise Are there anyone having the same problem?

 

Had you given the SEARCH box a try, you would have found out that this problem is the fan RESISTOR, and has absolutely nothing to do with this thread.

YOU need a new circulating fan resistor pack.