I need help guys..AC and temp sensors.


Passed Driver's Ed
I have an '08 GTI FSI....I noticed the AC wasn't working when I bought the car a year ago.. I also noticed that the bumper wire harness was missing.
-The harness connects the fog lamps and the outside temperature sensors-

I took my car to a mechanic to fix the AC issue...he recharged it, check'd for leaks, everything seems to be fine, the AC works now, but not the way it is supposed to. AC is not as cold as it should be and the fans do not turn on when they're supposed to. We check'd all connections, relays, etc etc....the missing harness and outside temp sensors have to do anything with this issue?

Any input would be greatly appreciated.

Thank you very much.


Ready to race!
there's a RCV in the AC that often goes bad. some ppl has replaced that and fixed, and others have replaced the whole compressor, condenser and drier.

I think the second is the way to go. but correct me if wrong.

Also the rad fans go bad, first the smaller, and when replacing the smaller it kills the bigger. Its supossed that both fans run in tandem not only one at a time.


That's what she said
Virginia Beach, VA
2008 GTI
You can do a fan test with VCDS. Make sure that both fans run through the full speed range. If either fan doesn't run you need to replace it. They are relatively easy to replace yourself by dropping the entire assembly out the bottom. The next thing to replace will be the high pressure sensor switch. You can do this from above without evacuating the AC system and the part is about $35. Finally, the refrigerant circulation valve could be going bad. It regulates the amount of refrigerant that is circulated and commonly gets clogged or sticks. The RCV is actually in the compressor but can be replaced. The dealer will just tell you that the entire compressor needs to be replaced. That's bullshit. The RCV is about $65 but you'll need to have the AC system evacuated before you replace it. Also, I had to pull my fan assembly again to have enough clearance to pull the RCV.

Replacement fans -
High pressure switch (1K0 959 126 E) -
RCV (likely EX019 for your 2008) -

Make sure you get the correct RCV based on the make of your compressor and the fastener type - snap ring or bolt. My 2008 used the snap ring type EX019 for a Saden compressor
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