Hello,

I have a 2009 XF Supercharged. About two months back I was driving and heard a loud metal piece fall to the ground. I pulled over and immediately noticed it was my AC Compressor Clutch, this was verified by my AC not working on the way home, everything still ran fine however. I sent it to a local Prodrive to get the AC compressor replaced ($800+) and when it returned the AC was still not functioning. I had a second shop look at it and they ran all the codes and said it was something electrical that they couldn't diagnose.
I don't have much money to go straight to Jaguar for service since I recently started school again. Any ideas what the problem could be here, I stay in Texas and being without AC and leather seats are not a good combo. Thanks!

 

Where you say "replaced" I'm assuming this means you have a brand new compressor, so the chances of it being faulty are unlikely (but not impossible). I have to ask - when you found it wasn't working, why didn't you take it back to the place that replaced it? I assume they delivered it back to you on the premise it was now working.

Do you have a code reader or a list of the codes that were stored? I have a 2010 and I'm guessing (but not certain) that the AC system is different on your 2009 so not sure of how much help e.g. the workshop manual sections I have for the 2010 on diagnosis are.

I'm assuming the second shop will have tested that all the really basic stuff like there's (e.g.) still refrigerant in the system etc. At the end of the day, the AC compressors are pretty simple - it's a pump with a clutch on it. If there's refrigerant in the system, it only needs the clutch energized to pressurize the system and then the air blows cold.

Can you hear the clutch/pump engage when you turn on the AC? (or have someone else do it with you standing over the engine - make sure it's specifically turned off in the climate menu first for this test).

If you can't, my first port of call would be to check:

• The wiring harness to the AC compressor, in case the first shop damaged it during fitting. Maybe the tech forgot to disconnect it before undoing the compressor and it hung on the harness, backing the pins out of the plug, or breaking a wire. You'll need the wiring diagrams for this model (worst case you can pay to get these from Jaguar, costs about $30ish for an hour of access to the site) and a multimeter. The compressor is likely controlled by the ECU but the wiring diagrams will confirm
• Wiring to the AC pressure switch
• Coolant temperature sensor (If the ECU doesn't know what temperature the engine is, it will prevent the AC from running to avoid accelerated overheating if there is a cooling problem).