I know this is an old thread but one to which I never said "thank you". I was driving across country, moving from Md. to Az. in the summer of 2013 when the A/C light started flashing and no A/C. I went to a dealer in Knoxville, Tn, my first night of stopping and was told my compressor was shot, new one was $1200 installed
. Decided to go online and research the issue and found this thread. Swapped two of the relays in the box and once again had A/C. Called the same dealer and they said such a failure was very rare but the relay would be $180 to replace
. Went to the Advance Auto down the street from the hotel, bought the aftermarket equivalent for $9 and is has worked to this very day. So because of this forum, went from a BS quote of $1200 to a slightly less BS quote of $180 to $9. I really needed that A/C through Texas, NM, and Arizona. So even though it's many years late, my thanks to the people who started this thread and figured out this problem to begin with.