I do not usually inject myself into Carrt's postings but Ihave a question on your AC. When you press the AC button and the fan is on, Is the AC light illuminated (on) inside the AC button? It the answer is "yes" then when the fan switch is turned all the way counter clockwise does the fan stop and the AC light go "OFF". It is the light going off that I am really questioning. If the answer is "NO" the light stays on, then you have a bad dround connection probably in the splice pack mounted behnd the air cleaner on the passenger side inside fender. I have seen this problem severakl times. If it did go off from turning the fan switch (not pressing the AC button), then you can ignre this entire posting.
A/c help
New to Colorodo life. A/C was working good. I just bought truck. LSA swap, cleaning up some wiring .
And now my a/c won’t kick on? I tryed testing the fuses? Good, relay good. Jumped relay and A/C kicks on? So does that mean my HVAC control is bad?? Ho do I test?
And now my a/c won’t kick on? I tryed testing the fuses? Good, relay good. Jumped relay and A/C kicks on? So does that mean my HVAC control is bad?? Ho do I test?
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Back on Mar 9th I posted in this because of your comment of when I press the AC button the light will not turn on. I hope you saw it, but you just never replied. That light is turned on ONLY when the fan is in position one or higher,,. NOT in the lowest OFF position. The light is controlled right there in the HVAC module by the blower switch along with the AC switch . To turn it off, the lead from the fan switch off position to the logic portion of the HVAC module is grounded (-12 volts DC). The absence of the light on tells me that either the bulb is bad, you have the fan switch in the off position, the blower motor switch is bad (probably shorted) or that lead is grounded by the HVAC control module.
The lead leaves the blower switch on pin A of the HVAC module, and runs on a dark green wire that returns to the logic portion of the HVAC module on PIN 7 labeled on the schematic "OFF BLW MTR CONTROL". With that line grounded, the HVAC module is never going to tell the BCM to turn on the compressor.
So until you can get that light to turn on and off correctly, nothing else you check is going to work to fix your problem.
If you do end up replacing the module, be careful. I got one from an 06 to put in an 05 and they were different. I ended up robbing the switch out of the 06 module and putting it in the original 05 HVAC module.
Good Luck
The lead leaves the blower switch on pin A of the HVAC module, and runs on a dark green wire that returns to the logic portion of the HVAC module on PIN 7 labeled on the schematic "OFF BLW MTR CONTROL". With that line grounded, the HVAC module is never going to tell the BCM to turn on the compressor.
So until you can get that light to turn on and off correctly, nothing else you check is going to work to fix your problem.
If you do end up replacing the module, be careful. I got one from an 06 to put in an 05 and they were different. I ended up robbing the switch out of the 06 module and putting it in the original 05 HVAC module.
Good Luck
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