Electric fan stays on

bilsan330 · 29th February 2016, 21:37

My 75 estate has suddenly developed an annoying problem the electric cooling fan intermittently comes on and stays on until I switch engine off. When you start the engine again it rights its self and stays off Then it can go days without it happening again or it could come on a couple of times during the car journey. The car does not overheat and runs at normal temperature.

Any ideas/suggestions or help would be very appreciated. Thanks Bill

T-Cut · 29th February 2016, 21:48

I assume yours is the later resistor type fan motor? Do you mean it always starts spontaneously? Is there nothing obvious that triggers it? For example, do you always have the aircon set to Auto?

TC.

stocktake · 29th February 2016, 21:56

Cooling fan will run whenever screen demist is selected, regardless of engine temp. Could it be you have just noticed it? The rad fan is also in use during A/C use

bilsan330 · 29th February 2016, 22:36

The year built is 2003 1.8 Turbo....Yes it seems to start spontaneously however I cant remember if it starts and will not stop after I have the air con on I will have to check..Anyway I turn everything off but the fan still runs it will not cut out or stop until I stop the car and switch the ignition off..I can then hear it slowing down and it stops. I wait a min then start the car and its ok...The temp gauge goes to normal and off we go then it can happen al over again..I have experimented with running the car with every thing off but it still happens.

What I want to know is when I take it to the garage what clues can I given them...because its an intermittent fault and they are hard to find...

Help please. Thanks Bill

RogerHeinz57 · 29th February 2016, 23:17

My car has developed a similar habit last year, Phil T-4 took a look at it for me, and suggested that the control box may have developed a problem causing the fan to run constantly with ignition on position 2 (With or without engine running) ATC unit all off still running. The temporary fix has been to remove the main fuse from the engine bay fuse box, this has stopped the fan going. The fix I hope is the control box (Which I have) but will need to do a front off to get to the box

bilsan330 · 1st March 2016, 08:45

Hi Thats seems to be the same as mine. I thought it might be something to do with the air con/demist switches...so I turn everything off went for a drive got the car up to temp....did not happen the first time but the second time went I got into traffic the electric rad fan came on then stayed on until I switch the engine off started again the fan stop and everything was ok until the next time. The fan stops after I start the engine again it could go all day without it happening again...

So what needs to be fixed is it some switch thats fautly....

Help please thanks. I cant keep stoping and starting the car.

SD1too · 1st March 2016, 22:34

Bill,

Your problem won't be the same as John H as he has a diesel control box which is a different design.

Start by activating the instrument pack diagnostics like this and note at what temperature the fan starts running. Keep the a.c./heating system in 'Econ' mode.

Also check your coolant level in the expansiontank.

Simon

29th February 2016, 21:37	#1
bilsan330 Avid contributor Rover 75 Estate Join Date: May 2015 Location: Ickenham Posts: 128 Thanks: 17 Thanked 8 Times in 8 Posts	Electric fan stays on My 75 estate has suddenly developed an annoying problem the electric cooling fan intermittently comes on and stays on until I switch engine off. When you start the engine again it rights its self and stays off Then it can go days without it happening again or it could come on a couple of times during the car journey. The car does not overheat and runs at normal temperature. Any ideas/suggestions or help would be very appreciated. Thanks Bill

29th February 2016, 21:56	#3
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,587 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	Cooling fan will run whenever screen demist is selected, regardless of engine temp. Could it be you have just noticed it? The rad fan is also in use during A/C use __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident Last edited by stocktake; 29th February 2016 at 22:00..

29th February 2016, 22:36	#4
bilsan330 Avid contributor Rover 75 Estate Join Date: May 2015 Location: Ickenham Posts: 128 Thanks: 17 Thanked 8 Times in 8 Posts	Electric fan problems The year built is 2003 1.8 Turbo....Yes it seems to start spontaneously however I cant remember if it starts and will not stop after I have the air con on I will have to check..Anyway I turn everything off but the fan still runs it will not cut out or stop until I stop the car and switch the ignition off..I can then hear it slowing down and it stops. I wait a min then start the car and its ok...The temp gauge goes to normal and off we go then it can happen al over again..I have experimented with running the car with every thing off but it still happens. What I want to know is when I take it to the garage what clues can I given them...because its an intermittent fault and they are hard to find... Help please. Thanks Bill

1st March 2016, 08:45	#6
bilsan330 Avid contributor Rover 75 Estate Join Date: May 2015 Location: Ickenham Posts: 128 Thanks: 17 Thanked 8 Times in 8 Posts	Fan problems Hi Thats seems to be the same as mine. I thought it might be something to do with the air con/demist switches...so I turn everything off went for a drive got the car up to temp....did not happen the first time but the second time went I got into traffic the electric rad fan came on then stayed on until I switch the engine off started again the fan stop and everything was ok until the next time. The fan stops after I start the engine again it could go all day without it happening again... So what needs to be fixed is it some switch thats fautly.... Help please thanks. I cant keep stoping and starting the car.

1st March 2016, 22:34	#7
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,372 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Bill, Your problem won't be the same as John H as he has a diesel control box which is a different design. Start by activating the instrument pack diagnostics like this and note at what temperature the fan starts running. Keep the a.c./heating system in 'Econ' mode. Also check your coolant level in the expansiontank. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

29th February 2016, 21:48	#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	I assume yours is the later resistor type fan motor? Do you mean it always starts spontaneously? Is there nothing obvious that triggers it? For example, do you always have the aircon set to Auto? TC.

29th February 2016, 23:17	#5
RogerHeinz57 I really should get out more....... A Reasonably Priced Car Join Date: Jan 2014 Location: Burton Latimer Posts: 2,530 Thanks: 408 Thanked 1,064 Times in 712 Posts	My car has developed a similar habit last year, Phil T-4 took a look at it for me, and suggested that the control box may have developed a problem causing the fan to run constantly with ignition on position 2 (With or without engine running) ATC unit all off still running. The temporary fix has been to remove the main fuse from the engine bay fuse box, this has stopped the fan going. The fix I hope is the control box (Which I have) but will need to do a front off to get to the box