Hey guys, I've been looking around the forums for this but I can't find anything conclusive. I've had my 04 2.5 x-type for a year now and ever since I bought it, the AC has a mind of it's own. you can leave it set at the same temperature and it would work fine for a while then all of a sudden the a/c compressor shuts off and the system starts blowing hot air. sometimes this would remedy itself in a few minutes and sometimes it never goes back to normal. I've played around with the system and i found that If you shut the car completely off and turn it back on the system works perfectly again for a while before doing the same thing. I never had the freon checked but i don't think its the freon since it blows really cold air and works when you restart the car. I'm thinking it is a wiring problem.

 

If the a/c compressor is "shuting off" as you say then maybe the compressor is overheating and the thermal switch is opening. Mine was quite noisy (clicking when compressor is running) until I added some oil. Have it checked by a good a/c shop.

 

Had similar problem with my '07 x-type. When ever the engines rpm would be low the system would start blowing hot outside air. Jag dealer (I'm covered by extended warranty) found the compressor to be bad. Have to drive in "Sport" mode until new part arrives. pophen

 

I don't think it's a problem with the compressor. I've gone on 6 hour trips where the A/C blew cold air constantly. and it doesn't have to do with engine speed as sometimes it would cut out on the highway at high RPMs. I'm thinking it may be the wiring to the control unit. I read a while ago that that is a common problem?

It's also not an interior temperature sensor because the fan speed fluctuates correctly, with or without the A/C working.

 

If you know the answers then why did you ask the question? Just tell us what was wrong when you've got it fixed.

 

I'm not sure if thats the reason. I'm looking for other opinions and if anyone has had a similar problem that they've had fixed so I can see how to fix it.

 

My HVAC does the same thing in AC mode now and then. I looked in the service record the previous owner gave me and found back in 05 the Jaguar Dealer he used had to re-flash the computer, as the complaint was the AC ran inconsistently cold them luke warm and then cold again. Someone wrote on this forum to check the fan speed. Put you AC on manual and turn the fan knob all the way to as high as it will go and set the temp to LO. Then open the hood stand in front of the car and put your face down toward the fans, the person said you should get a blast of air from the fans, if not you fan control module is not working properly, you can see it if you look down into the fan it is on the right side if your facing the car, it is a metal box with wires on both side and is sort of a sort of brass color, doesn't look too hard to change.

 

I'm telling you it is either a computer problem or a fan switch is wearing out. I had my AC checked yesterday and the system is full, I had the tech recharge the system, he completely flushed it out and replace with fresh coolant. It was 19 degrees F at the vents when I left. I got caught up in some traffic on the way home due to the damage from three tornadoes we had here on Friday. What a mess, anyway the AC started pumping warmer air. I put the car in park and revved the engine a bit and it started to cool down Then the traffic eased and no problem after that. This week is going to be a good test, by Thursday it is supposed to be in the 90 degree F range.Last summer the car got very warm even with the HVAC set a LO. But quickly cooled at speed increased. Why AC systems kick out on the highway or under acceleration, they are still partly run by engine vacuum. When you load up the engine as when speeding or fast acceleration the compressor will kick off for a few seconds and when the load is normal switch back on. Also, if the fan switch is bad you might not notice any increase in engine temp on the gauge as both coolant and at least one fan is running when the engine is warm. My temp dial when the engine is warm is pegged at the halfway make, winter of hot, hot summer days, in traffic or at 70mph.

 

had the compressor replaced under extended warrenty last summer i think because it was leaking oil.
although i dont think its your compressor, it sounds like a electrical issue. maybe a interior temp sensor or a relay that is wearing out. it could even be your climate control unit, ive heard of those going bad and sending false signals in other cars.