Radiator fan problem.

**bam87** · 19-10-2010, 10:10 PM

Hi Guys, having a problem with the radiator fan not turning off when i turn the cars ignition off. I have to physically pop the bonnet and disconnect the plug to the fan. Any idea's on what to do to fix this??? (I have already looked at my fuse box, and its not wet or fried). Ironically this happened wed last week when there was massive downpour.

VW Golf 1990, GTI.

Cheers, Blake

**ryana89** · 19-10-2010, 11:16 PM

Straight out of a Bentley Workshop Manual for this model car.....

"On some models with gasoline engines, a cooling fan after run system, operated by a control unit on the fuse/relay panel, runs the cooling fan for as long as 15 minutes after the engine is shut off, as a guard against starting problems which may be caused by high engine compartment temperatures".

Its normal, and a feature many older European cars have.

**walshydub** · 20-10-2010, 08:08 AM

Originally Posted by ryana89

Straight out of a Bentley Workshop Manual for this model car.....

"On some models with gasoline engines, a cooling fan after run system, operated by a control unit on the fuse/relay panel, runs the cooling fan for as long as 15 minutes after the engine is shut off, as a guard against starting problems which may be caused by high engine compartment temperatures".

Its normal, and a feature many older European cars have.

Yep, he's right they all do it. All my Mk2's have done it from a 1.3 to 16V GTI
You are probably doing more harm by disconnecting the fan...

**RedMk2Gti** · 20-10-2010, 08:27 AM

I don't 100% believe that, if the fan keep running up to 15 minutes after the engine is stopped something must be wrong. The longest that I've seen in my car is about 1.5 minutes.

**walshydub** · 20-10-2010, 10:15 AM

Mine can run for up to 5 minutes on really hot days. Sometimes it runs for a minute or 2, stops for a few seconds the starts up again for a few more minutes. It's never bothered me as all my MK2's have done it.
15 minutes would be a little extreme but the fan would keep running until it got the temp down to a level where it would automatically shut off.
I don't think it is anything to worry about but unless it keeps on running without ever switching off.

**ryana89** · 20-10-2010, 01:39 PM

Its the job of a little sensor in the back of the engine bay (near the manifold) that decides when the fan run on feature is engaged or not, according the the Bentley Bible.

I think 15 minutes might be possible if the car has been red lined or been doing extremely hard work for the past 5 minutes and if the outside temp is high (say in the 40's)

**brad** · 20-10-2010, 02:51 PM

The others are right but if it runs beyond 15 minutes then the sensor is probably dead. IIRC, on failure, the circuit is closed. I guess they figure you are better off with a flat battery instead of an overheated engine.

**bam87** · 20-10-2010, 05:18 PM

Hi guys, i knew that the fan usually ran after the car was switched off, mine used to only cool for about 2mins then switch off, but as brad said, it ran my car dead. i have tried letting it run to switch itself off but the fan just keeps running unfortunately. Anyone know what it cost to fix/replace the sensor?