QuestionHAD NEW COMPRESSOR W/CLUTCH INSTALLED,SYSTEM IS FULLY CHARGED BUT BLOWS A FUSE IN FUSE BOX WHEN EVER AC IS TURNED ON. AC SHOP STATES ITS NOT IN THE COMPRESSOR, CLUTCH OR RELAY....ANY SUGGESTIONS?????
AnswerDavid,
Is this something that it was doing prior to your compressor being replaced? Is it the A/C clutch fuse blowing, or is it shutting down your blower motor also?
There are only two things in your A/C electrical system that will cause a current draw large enough to blow your A/C clutch fuse. One of course is the comressor clutch itself. If your clutch coil is shorting out it will cause a huge drain and blow your fuse quick. As will a short in the wiring harness itself. These are the only possiblities. And yes, occasionally you will get a bad clutch on a new compressor. Quality control just isn't what it used to be.
How did the shop verify that it wasn't your clutch causing the short. The easiest way, though it sounds a bit on the shade tree mechanic side is as follows...
Disconnect the harness plug from the compressor itself. turn the A/C on. Did your fuse blow? If it did, then the problem lies in your wiring harness itself. Check your harness for any obvious eye-grabbers, such as where there may be any melted insulation. If there are no obvious signs... you will need a multimeter and do many continuity checks between harness/plugs and ground until you find where the short is.
If it did not blow your fuse with the compressor unplugged. It is definately your clutch coil. But to verify... Identify which of the connectors on the compressor itself is your voltage in. If you have a one-wire compressor it is your hot wire. Run a short jumper from your negative clutch terminal (not on the plug itself) to a good ground. Connect another jumper wire with the same size fuse in line with it from your positive terminal on the battery to the positive terminal on your compressor. Did it blow that fuse? If so... take it back to the shop and tell them to do the job again, but right this time. If it didn't then it is definately in your wiring harness.
Depending upon your knowledgability with electrical systems and experience in finding shorts in wiring harnesses, it may be to your benefit to take it to a reputable shop or even the dealer to have them troubleshoot it. It can be a lengthy process for the inexperienced.
I hope I was of a little help. Thank you for the question, and if I can do anything more, please let me know. Good luck in everything.
