Jaguar X Type AC Dead: Compressor Won't Engage

Having experienced a similar issue on a 2007 Jaguar S Type 2.7 Diesel with comparable mileage, the symptoms point to a failed AC relay switch or pressure sensor. The AC system on these Jaguars uses a safety pressure switch that prevents the compressor from engaging if refrigerant pressure is too low or too high. When the HVAC system lost pressure in my case, the pressure sensor triggered a failsafe, causing the compressor to stop engaging. The check engine light appeared because the pressure switch feeds data to the engine control module. The most common failure points in order of likelihood: 1. AC relay switch failure 2. Low refrigerant due to slow leak 3. Failed pressure switch 4. Compressor electrical issues 5. Complete compressor failure A proper diagnosis requires connecting to the vehicles computer system to read the specific fault codes. The pressure sensor and AC relay are relatively straightforward fixes compared to a full compressor replacement. However, if the compressor has seized, it becomes a major repair requiring system flush and replacement of multiple HVAC system components. Based on the symptoms described, start with having the relay switch and pressure sensor tested before assuming compressor failure. These Jaguar AC systems are fairly robust when maintained properly.

Thanks for the detailed reply about the AC system issues. The symptoms you described match mine exactly, no engagement and that annoying check engine light. After your message, I suspect it might be the relay switch or refrigerant leak causing the pressure sensor to act up. Can you remember roughly what the final repair cost was in your case? Also, have you had any other A/C system problems since getting it fixed? Want to know if I should expect more issues down the line with the belt tensioner or other components. This helps a lot with knowing what to discuss with the shop. At least now I wont walk in completely blind to potential causes.

After taking my Jaguar S Type to a certified shop, it turned out the A/C compressor shutoff problem was exactly what I suspected, an electrical undervoltage issue affecting the relay switch. The total repair came to 240€, which included diagnostic testing and fixing the voltage problem in the HVAC system. The repair has held up perfectly for the past two years with no additional A/C system problems. The A/C compressor now engages smoothly every time, and the check engine light has stayed off. The belt tensioner and other components have been running fine too. If your symptoms are similar, having the electrical system and relay switch checked first makes sense before replacing more expensive components. A proper diagnosis using the right testing equipment should pinpoint whether its the pressure switch or a voltage issue like mine was.

I took your advice and went to get it checked out at a certified shop last week. The technician confirmed it was actually the pressure sensor that had failed, likely due to a slow refrigerant leak that developed over time. This matched what you mentioned about the safety systems preventing compressor engagement. The total repair came to 380€, which included replacing the pressure sensor, recharging the refrigerant, and fixing a small leak they found in one of the lines. The A/C compressor kicked right back in after the repair and has been working great since. The check engine light is finally off too. Really glad I didn't just assume the worst about needing a full compressor replacement. The shop seemed honest and walked me through their diagnostic process. They even showed me how the pressure sensor interfaces with the AC relay to protect the system. Definitely feeling more confident about maintaining the car now and knowing what to watch for in the future.