guaranteeI first took it to Sheppard Motors in Eugene, Oregon, where we bought the car and had all required maintenance done, and asked them to fix the air conditioner. I told them what the problem was, that it would cool then put out hot air, then cool, but never staying in the cool mode. All they did was "ACER AIR Conditioning - Evac and recharge 3100 CPW", I had already done that, and they charged $110. They also refilled at as cost of $32 for a total cost of $142. (90662 evacuated the ac system and vacuum tested for leaks. Found no leaks present at this time. Charged system and tested the AC. AC system.) They then took if for a test drive and reported "Is not currently blowing cold. Hi and Low side pressures are static at approx. 80psi...During test drive I found the AC to intermittently blow cold air." in other words it wasn't fixed.

I found out from a young lady at Kar Kare in Port Orford, Oregon, that she had a similar problem with her air conditioner in her truck (Not a VW Product). She told be it was the sensor in the conditioner pump and when it was replaced it worked great.

I went on line and found the same problem for the VW Jetta and instruction on how to replace the sensor.

I the took the car to Franklin Waterman of Waterman Automotive, in Bandon, Oregon and asked him if he would be able to fix the condition problem. I told him what I had found on line. He spent an hour of his time (cost me $85) and he discovered the problem I was talking about but there was only one problem: there was only one manufacture in the country that would supply the part needed. The part only cost about $35 plus shipping. He asked if I wanted to go that route as there was no guarantee that would fix the problem. I said go ahead. The part arrived a week later, and Mr. Waterman installed and for about $400 (including the cost of the part, shipping and his labor and recharging the system.) Has worked great ever since. Mr. Waterman told me he found out that there is a weak spring in these sensors installed in VW air conditioners that are starting to fail.

According to VW factory diagnostics manual, the problem is a faulty temperature sensor, bad wiring from the senor to the ECU or bad ECU. I had the temperature sensor replaced but the CEL light came back on two weeks later with the exact same diagnostic code: Engine Coolant Temp Sensor on Radiator Outlet (G83) P2185 - 002 - Signal too High. Diagnostic data shows initial sensor reading -90 degrees C followed by values changing more than 20C between samples which doesn't seem possible seeing how the engine was cold and not running when I ran the diagnostics.

I replaced the sensor a second time and the same error occurred again. On a 2 year old car, with only 50K miles, how could it develop faulty wiring or need a $1000+ ECU replacement. The really strange thing and I am hesitant to mention it but I noticed this last time, the CEL came on after braking hard. I also had a different error code occur after braking hard about 6 months ago, had it cleared and it didn't reoccur. This makes me think that the connector(s) to the ECU might not be seated completely or it's an intermittency of some kind. My next attempt will be to check the continuity between the sensor connector pins and the ECU connector pins. It should measure no more than 1.5 ohms pin to pin. If the wiring checks out, the only other part is the ECU.