A/C Help????
A/C Help???? Guys,
Have a weird one for ya. After my radio install my AC clutch won't engage/the AC won't cool. Did some trouble shooting and tested the low pressure switch and it was fine, took out the relay and jumped the AC compressor and it runs fine and cools the car down ice cold. So I thought it was a bad relay, but no!!! After replacing the relay the clutch still won't engage on the compressor, but if I take out the new relay and jump it again, wham - the AC works? Does this sound like I have a bad switch in the HVAC console? Any ideas would be greatly appreciated as it's getting hot here in Houston - 95+ today.
Have a weird one for ya. After my radio install my AC clutch won't engage/the AC won't cool. Did some trouble shooting and tested the low pressure switch and it was fine, took out the relay and jumped the AC compressor and it runs fine and cools the car down ice cold. So I thought it was a bad relay, but no!!! After replacing the relay the clutch still won't engage on the compressor, but if I take out the new relay and jump it again, wham - the AC works? Does this sound like I have a bad switch in the HVAC console? Any ideas would be greatly appreciated as it's getting hot here in Houston - 95+ today.
TECH Enthusiast
Joined: Jun 2004
Posts: 597
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Pull the HVAC plug off the switch, check the contacts, maybe clean them with a wire brush(switch side!) and reconnect it. possible as you installed the radio you somehow dislodged the HVAC control plug. That or skinned one of its wires and shorted it.
Thanks for the help, but I think I found out the problem. My system was so low on freon that my low pressure sensor set a code in the PCM. Jumped the relay to get the compressor started and recharged the system. Then unplugged the batt to reset the PCM and clear the codes. After that reconnected the PCM and fired her up. The compressor kicked on right away when I switched on the A/C and blew ICE COLD. Guess I just had a code in the PCM that was keeping it from coming on. Didn't have access to my computer and cable so I wasn't able to actually view the code, but it had to have been a low pressure indicator.
TECH Enthusiast
Joined: Jun 2004
Posts: 597
Likes: 0
Cool, at least you got it fixed. It is possible there is a sensor for freon(not really freon anymore, but everyone even my HVAC subcontractor company calls it that..) that prevents the compressor from kicking on. You simply bypassed that sensor, interesting know one exists. my plate tamper and other stuff has a low oil cutoff sensor in it without a PCM. just a float switch.
