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Paul_540i
04-02-2005, 11:43 AM
Where do I start? It's never seemed to work since I picked up the car a few months ago. Today I changed the microfilter (vast improvement in airflow) and noticed the air definitely isn't cold. Had a look under the bonnet with the A/C switched on and neither the compressor is spinning nor the auxilliary electric fan.

I also noticed the aux fan cannot be spun manually when the car is parked, is this normal or has it seized?

Cheers
Paul.

SRR2
04-02-2005, 12:18 PM
The AUX fan should spin freely. There are a couple of common reasons why the compressor won't run. In no particular order: Low refrigerant charge. Blown fuse in clutch circuit. Burned-out clutch. Seized compressor. Troubleshooting these is very straightforward with a multimeter. I'd go the fuse route first since the seized AUX fan prolly blew its fuse and may have disabled the system as a precaution. You'd have to follow the wiring diagram to see about this for sure though.

Javier
04-02-2005, 08:43 PM
(1994 drawings as don't know your year model) and it is not related to compressor clutch. Think both issues are independent.

Main cause is low pressure, ask for a gas leak test and refill as necessary.

Javier

Paul_540i
04-03-2005, 05:38 AM
Thanks for the info. Mine is a 1995. I'll have a look at the fuse for the fan, but I guess I'm looking at getting a replacement aux fan then? I may try giving it a little force as there's nothing to lose if I break it, but I guess it's shot anyway even if it does free up.

Paul.

Javier
04-03-2005, 07:07 AM
what is going on with the fan, and as you said, fooling a little bit with it, will not get it any worse.

Javier

Paul_540i
04-03-2005, 11:26 AM
Strangely I checked the fuses for the aux fan (there are two listed on the fusebox cover) and both seem fine. Can't budge the fan though, quite difficult to get at it without removing the bumper or grille.

Javier
04-03-2005, 11:35 AM
F29 (7.5A) powers the fan relays coil (also A/C clutch relay coil and auxiliary water pump relay coil).

If fan is seized or short-circuited, F25 will blow out unless relays are not operating.

Removing the bumper is the way to gain access.

Javier

Paul_540i
04-03-2005, 01:07 PM
Thanks will have another go next weekend.