Check fuse #21 (underhood fuse box).
If it is good, swap the A/C relay with another identical relay (likely it’s one in that very same fuse box).
Now turn on the a/c (engine running) to see if the compressor engages.
If not, use a voltmeter or testlight ot check for power at the a/c compressor clutch { this has to be done with the engine running and the a/c on}
BE VERY CAREFUL WILE WORKING ON A RUNNING ENGINE!:
unplug the electrical connector at the a/c compressor clutch.
You should have 12v on the DB/YL (dark blue/Yellow stripe) wire with the engine running and a/c switch on. (Of course this is dependent upon whether or not the system has enough Freon in it to create pressure (the pressure switch has to sense pressure before it will allow the compressor to turn on). The black wire at the compressor clutch is the ground wire.
If you have 12v there and still the compressor will not turn on, suspect a faulty compressor clutch.
If you don’t have 12v there, suspect that the system is low on Freon (R-134a) or that there is a open in the DB/YL wire (this is very rare).
Please post your results here for more help.
Jul 4, 2013 at 7:38 PM
