So I have a 2004 tahoe LT with the dual auto air controls. Ac has been recently recharged, and all was working fine. The control module though had a few lights out, and the dials were a bit temperamental. I picked up a used OEM one on ebay to solve these problems but whe. I installed it, it didnt work correctly. After checking the model numbers I realized the one I ordered was slightly different though it looked the same. I sent it back and put the original back in, but now my system will only blow hot air? I tried the recalibrating procedure listed here five or six different ti.es now with no improvement. Any suggestions?
There could be several things going on. First I would recommend checking to make sure that the fuses are good. Next since your vehicle has auto controls, does the digital display default to 74 F when the recalibration is started? Is the temperature problem present on both sides of the dash?
If those are all okay I would recommend visually inspecting the four actuators to see if one or more successfully moves. The problem that can sometimes happen is that an actuator can fail to recalibrate and set a code. If this happens early in the process the remaining actuators will be stuck.
With all of that said the obvious thing to do would be to install a known good control panel that is also the correct part number.
If need be you can use the information in the following article to see if you can manually make the actuators move.
So upon looking back into the problem. I can say that the fuse is fine, and the controls do reset to the 74 degree setting and seems to go through the actuators adjustments. I did notice something new today though that I failed to notice before as I wasn’t looking for it. I noticed that the compressor clutch is not kicking on. I have checked the fuse and relay for the clutch and those are good, and getting power. I have not tested out the high and low pressure switches just yet, as I have another (correct model) controller arriving tomorrow that I will try before getting into anything else. Do you think there is a real possibility that the controller with the wrong part number could’ve damaged the switches or worse, the compressor clutch itself? It was working normally before I switched it out.
I doubt that the incorrect controller would have damaged anything in the system beyond possibly blowing a fuse and you have ruled that out.
Yeah, I wouldn’t think so either… I will let you know after I have swapped the controller if that fixes it. If not I’m at a loss as to how the clutch isnt related somehow, but I always seem to get vehicles with electrical gremlins living inside so I guess I shouldn’t be surprised!