Manager Forum

A/C COMPRESSOR WAS BURNT UP WHEN THE CAR CAME IN.

CHANGE COMP. DRYER, ORFICE AND FLUSH SYSTEM. COMPREESOR AND HIGH PRESSURE SWITCH NOT GETTING POWER FROM COMPUTER. RELAY IS GOOD, NO FUSES BLOWN.

ANY HELP WOULD APPRECIATED

Pull ac relay out and see if its getting a trigger from pcm. if not then check at pcm and inspect pins and terminals. If still nothing then most probable is pcm but check to see if all ac inputs being received by pcm

You say the high pressure switch is not getting power from the PCM. Are you referring to the 5 volt reference? That should be present on the grey wire. If it is not there at the sensor, check right at the PCM. The PCM controls the ground on the relay to power up the compressor after the switch inputs. You can check the power side of things by grounding the relay and seeing if the compressor comes on. That should be the Drk Grn.Wht wire at the relay. I like those relay testers that you can piggy back a relay onto. They have nice test tabs on them.

i grounded the relay out and everything works fine. I am getting signal from a/c button, but not to pressure switch or a/c compressor.

You need to hook up your scan tool and see what the reading on the pressure trtansducer for the a/c system is, have seen several of these with wireing issues to this sensor and it will read zero on the scanner.

if there is a code it may be shutting down the system...............

sounds like pcm not sending trigger to relay. ac button sends signal to pcm.

fixed it was the pcm

Thanks for posting the fix!

ditto