2004 Suburban A/C Question

chevrolet
suburban
2500
airconditioning

#1

My 2004 Suburban 4x4 3/4 ton was recently stolen and recovered, less the outside mirrors, gauge cluster, and Radio/CD Changer. Insurance paid to put it all back together with new parts.



However, I noticed that when I run the A/C (usually at about 72 degrees), the A/C air will suddenly switch to about 90 degrees for about 5 seconds or so, then go back to the normal 72 degrees. It does this every 10 minutes or so.



Since ‘busy hands’ were messing around under the dash while removing my valuable parts and while doing the repair work, I am a little suspicous that something got messed up. Any thoughts on what to look at?


#2

AS always I would look at the low pressure cut off switch. Have the hood open and note if the temp changes match compressor operation.

You must be dealing with an automatic climate control system, this also would be a very good place to start, along with TSB’s.


#3

I did check TSB’s for you and there are 64 different HVAC TSB’s for your Suburban. Now some are general "how to check this or that " but boy oh boy GM sure makes a great one.

There are 2 TSB’s that really could apply to your situation, one deals with inability to set driver and passenger temps the same but with this one I get a “file not found” message and the second deals with test procedures for the low pressure cycling switch.

There you got a bump.