I am having a cooling problem with my A4 B6. When I was driving I noticed the A/C was blowing but not as cold as it used to, it would just blow regular air with no cooling. As I stoped at a red light the coolant alarm went off on the DIS, and as I looked at my temperature gauge it was 3/4 hot. I immediately pulled over and turned off the car but there was no smoke and the water and oil level were fine. What could have caused this? does the A/C not cooling have anything to do with it? I would appreciate any feedback. Thanks

 

1. Check that the electric fan is going on when the AC is on and the car is warm. If not, that is your problem.

2. If not, then your water pump may be going bad.

 

Ac will shutoff when engine temp gets to hot. Rest of diagnoisis is as david9999 said. Also check the mechanical fan. It should spin pretty fast when the engine gets to normal operating temp.

 

Thanks for your relpies guys. Just as you mentioned, the fan is not going off at all. What could be the problem? still the water pump, or more a sensor? Any help will be greatly appreciated. By the way, if it were to be th e water pump, the fans would still come on right? I think it might be more of a senor problem because both fans do not come on.

 

The main fan is a clutch fan, so it should run. The secondary fan that comes on when the engine is warm and the AC is on is electric. The motor generally burns out on it. You can check the fuse which is a 40A (as I recall) and is in the fuse bank behind the driver's side lower dash in the secondary fuse box. Likely the fuse is burned out. You can try to replace it. The motor should start turning when the engine is warm and the AC is on. If the fuse blows in a minute or two, then the motor is bad. Replacement fan is about 125 dollars.