QuestionThe A/C quit working after just using it. I have R134 gauges, vac pump, & leak detector. I checked fuses, freon level, and found no power to compressor. Putting power to compressor it works and cools. The temp goes to hot and cool and all the flaps are working. I think the compressor relay is out to lunch.
I am an ASE master that just retired from a Porsche dealer, so asking a question this is humbling.
Question: Where are the relays located? The owners manual nor a Haynes gives it.
AnswerBefore looking for relays, bypass the pressure switch, which is usually on the accumulator or in the low side line, see if that turns the comp. clutch on. These were common failures. You can also verify voltage at this switch with a test light or voltmeter, engine running and ac switch ON. The ac and other engine relays are in the CCRM, you'll find it behind or next to the coolant bottle. Haven't seen many of these fail, although if you don't have power at the pressure switch it could be the CCRM.
(Constant control relay module)
Don't feel bad about asking, my youngest daughter drives an Audi A4. I couldn't begin to figure that sucker out.
