Whether manual or automatic system, the A/C compressor gets its power supply from the A/C compressor relay and there are 3 possibilities for the relay to be energised.
1. Faulty relay. It is self triggering intermittently and contacting to provide power to the compressor. Try swapping out the compressor relay with the fog light relay and see if problem goeas away.
2. A short in the grounding circuit of the compressor relay. You would need to test orange wire for shorting.
3. Faulty PCM. It is grounding the relay intermittently.
Tuesday, September 13th, 2011 AT 12:00 PM