2009 Grand Marquis Ultimate Edition AC compressor stopped worki,
Asked by Andrew Jun 27, 2014 at 09:15 PM about the 2009 Mercury Grand Marquis LS
Question type: Maintenance & Repair
My AC compressor just stopped working, it was working fine 2 days ago then today it stopped and just blows hot air. I think I checked the correct fuses under the dash and under the hood but the owners manual pics/location layout aren't very clear but I did check anything AC related all fuses are good, I checked visually as well as used a continuity tester.
Does anyone know what else could be the issue?
4 Answers
Low Freon is most likely the culprit although, I have seen a couple of serpentine belts throw pieces and break the wires at the high pressure cut off switch too.
Trippmeister answered 10 years ago
A defective high pressure cut off switch would do it. I think they can be replaced without evacuating the system. Jumping the correct two wires would tell you. The older cars had only 2 wires, but the newer have 4 or more.
It was low on Freon, thanks I'm glad it was simple. It was just strange how it worked great one day then two days later nothing.
