Engine Fan & Aircon

Salmon · 26th November 2019, 03:13

Ive noticed recently that my engine fan comes on high speed for about 5 seconds and switches off again when my heater is on regardless of engine temp.
This repeats every few minutes. I really don’t remember this happening before and yet people are saying its normal.
I noticed it after having a new clutch fitted and I’m wondering if the mechanic connected every thing back properly.

T-Cut · 26th November 2019, 09:19

The 'slow' speed fan should run continuously whenever the aircon system operates. If by 'heater' you mean the aircon system then your fan has a fault. The usual cause of aircon fan pulsing at a 'high' speed is failure of the low speed circuit. The forum is full of threads on this, but the first thing to confirm is low speed failure. This is done by running the so-called Demist Test. Just do a forum search for this. Meanwhile, you should determine the type of radiator fan you have (the older 3-speed or the later 2-speed). The fix will depend on that. Look through the front grill and behind the fan blades (2 o'clock position) to determine if a low speed resistor is attached to the fan guard. Report back with that and you'll get a flood of advice. There's no connection between a new clutch job and the fan. Not usually anyway.

I believe this image is from Arctic

TC

Salmon · 30th November 2019, 16:59

That's great. Thanks

26th November 2019, 03:13	#1
Salmon Loves to post Rover 75 Saloon CDTi Connesuer Join Date: Mar 2014 Location: Winchester Posts: 424 Thanks: 251 Thanked 33 Times in 28 Posts	Engine Fan & Aircon Ive noticed recently that my engine fan comes on high speed for about 5 seconds and switches off again when my heater is on regardless of engine temp. This repeats every few minutes. I really don’t remember this happening before and yet people are saying its normal. I noticed it after having a new clutch fitted and I’m wondering if the mechanic connected every thing back properly. __________________ [SIGPIC][/SIGPIC]

26th November 2019, 09:19	#2
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	The 'slow' speed fan should run continuously whenever the aircon system operates. If by 'heater' you mean the aircon system then your fan has a fault. The usual cause of aircon fan pulsing at a 'high' speed is failure of the low speed circuit. The forum is full of threads on this, but the first thing to confirm is low speed failure. This is done by running the so-called Demist Test. Just do a forum search for this. Meanwhile, you should determine the type of radiator fan you have (the older 3-speed or the later 2-speed). The fix will depend on that. Look through the front grill and behind the fan blades (2 o'clock position) to determine if a low speed resistor is attached to the fan guard. Report back with that and you'll get a flood of advice. There's no connection between a new clutch job and the fan. Not usually anyway. I believe this image is from Arctic TC Last edited by T-Cut; 26th November 2019 at 09:35..

30th November 2019, 16:59	#3
Salmon Loves to post Rover 75 Saloon CDTi Connesuer Join Date: Mar 2014 Location: Winchester Posts: 424 Thanks: 251 Thanked 33 Times in 28 Posts	That's great. Thanks __________________ [SIGPIC][/SIGPIC]