Ok, a/c will work of o hot wire pump, and it blows ice out, but obviously it can't be run that way. Everything else works, any ideas where to look? Checked all fuses and replaced relays but no change, what's next?
Thx
Thx
Help: A/C not working
- Thread starter DieselDummy
- Start date
It's the small switch located on the accumulator(canister at teh A/C lines coming out of the firewall). Disconnect it and take a piece of wire and jumper across it, if it comes on then replace it. It should close at 50 PSI and open at 18-20 PSI.
ok i changed it with a new one and same issue, would anything in the dash controls cause it to not work. I dont have the digital controls, but all the lights come on.
Could be the high pressure switch over by the compressor, blown fuse, bad relay, or a wiring problem. Simplest thing to do is get a scan tool and see if it will turn on with the scan tool when you command it. If it does then you have a problem with the circuit telling it to come on. If it doesn't then you have a relay or switch problem. Also was this truck tuned since the A/C quit? If teh wrong operating system is flashed in then the ECM will not turn the A/C on.
Checked all fuses and relays all seem to be working, changed both pressure switches, it was tuned the day I bought it but. Never used a/c till last couple weeks and it's never worked. I can hot wire but it only works till head pressure overrides clutch pressure and it slips, it blows cold till then.
If it has the wrong tune in it, the A/C will never work right. 03-05's MUST use the correct base file in the ECM for the accesories to work.
He's right! my dads old 04 did this along with the oil pressure gauge quit working. Put the stock OS back and and BAM, Everything started working again.
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01-02 are the same way.
It will be the only thing that doesnt work. Ive been down that road and had it happen to me
I've done a few 01-02's, and I've always used a 6006 OS in them(all using the same base file) and never had an issue. Same with 06+. the 03-05's are some picky things though about having the EXACT tune file in them. Some lose cruise, others lose the A/C, and so on. This is why you must start out with the correct base tune file.
Yes, you just have to start with a stock tune file. Your only way to see if you have teh correct tune file is to read it out with EFILIVE, go to the TIS site and check the segments to see if they all match, or go to GM and have it flashed by them to stock and build tour tunes off of it.
Have you checked the plug that hooks to the clutch coil. One should be power the other ground.
Start tracing the wires back to see if there is an issue where one of them rubbed through or could have gotten broken.
Start tracing the wires back to see if there is an issue where one of them rubbed through or could have gotten broken.
I fought my AC for a loooong time. Replaced a lot of shit. What fixed it was replacing the in dash unit. Apparently something was crossed in there and one day it started smoking like crazy. Replaced it, instant freezer status.
i can put power to relay and it will run so i know its not a harness issue from there, we are gonna check tune, if that doesn't fix it, then im gonna try the dash switch's.