Slow speed fan problem - Guide to fixing

markpile

Wolves till i die!!!!
Mar 15, 2014
434
0
Wolverhampton
guys i have a question, as per previous reply, my fans work perfect when aircon is on a slow speed run, but with aircon off when car hits 93degrees they do a short slow speed pulse, i have the green engine stat and it looks new, so just taken car to bits and did a quick test 12v to the thiner red/white and slow speed runs for as long as i have it connected to my source, same with the thicker red/blk wire full speed fans running for as long as i have them on the source,

so would the resister still be faulty in the fans or is it something else

thanks mark
 

mattyglcr

Active Member
Oct 23, 2011
88
0
any one close 2 the midlands want to do mine i dont mind paying and feeding you tea and biscuits lol
 

Kambo

Active Member
Mar 28, 2013
197
0
Hants
guys i have a question, as per previous reply, my fans work perfect when aircon is on a slow speed run, but with aircon off when car hits 93degrees they do a short slow speed pulse, i have the green engine stat and it looks new, so just taken car to bits and did a quick test 12v to the thiner red/white and slow speed runs for as long as i have it connected to my source, same with the thicker red/blk wire full speed fans running for as long as i have them on the source,

so would the resister still be faulty in the fans or is it something else

This is the thing, they shouldn't be pulsing, if its on/off every five seconds or so once warm then you need the resistor mod
 

Crhome

Active Member
Dec 18, 2012
188
0
Nottingham
Sry for resurrecting. Hey olygt4, after doing slow resistor mod, have you ever noticed your fast speed kick in at all?
 

Ellis jack

Guest
Yes mate that's what I used. Don't have to splice, easier using blocks
 

rydogg09

lcr ry
Feb 5, 2012
403
0
where are the resistors mounted on the golf as I have fmic and no side mounted ones? thanks
 

Sean886

Active Member
May 15, 2014
371
0
If my fans dont work at all... would it explain why my aircon wasnt/isnt working?
 

Rob36

Active Member
Feb 16, 2015
5
0
Hi guys. I have a different problem than most in this thread. The fans start immediately on high speed on ingnition, and stay on. Could this still be the resistor problem? I had planned to change the thermoswitch and coolant sensor first but was pointed to this thread. I'm not too clued up on electrics, but determined to fix it so any pointers would be grand :)
 

Muttley

Catch that diesel!
Mar 17, 2006
4,987
31
North Kent
Morty - yes it will, but it is a very expensive way of solving the problem, and the underlying issue (the inadequate resistors incorporated into the fans) will remain - in other words, they are likely to fail again.

The resistor mod will fix the problem and prevent it from happening again.
 

Kambo

Active Member
Mar 28, 2013
197
0
Hants
As above morty, there is a reason your fans have failed and will do again eventually if you buy new ones, as mentioned the resistor mod will solve that, so keep your current fans, test them and if all ok do the resistor mod and bobs your uncle
 

Kambo

Active Member
Mar 28, 2013
197
0
Hants
I've added a couple of pics that I'm not sure why I didn't before, this should have been on page 2

This is from a diesel perspective but should hopefully be the same for the petrol models

Template made is 120mm wide at the top and 85mm at the bottom, 40mm depth from the top and 130mm depth for the bottom





Location is under the battery box hanging over the side







:)
 

Garreh

Active Member
May 17, 2009
28
1
Wolverhampton
I have a Ibiza 1.2 with the same problem and I'm going to apply this solution (Thank you!!) but there's one thing that I cannot get my head around with this.

Will the high fan speed still work if the car needs it?

**EDIT**
I've just realized how this actually works - From what I can see, the resistor mod is passing reduced voltage / current over to the HIGH speed fan wire, bypassing the LOW speed internal resistor. This is why the fan runs slower...

How much of a clown do I look now? lol
 
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Kambo

Active Member
Mar 28, 2013
197
0
Hants
Check out the trouble shooting on the first page, that will at least give you an idea of where your fans stand as they are

Mine was slow speed came on with air con but high speed never did, my temp never exceeded the point where the high speed was needed but it turned out thats because they wasn't working, never had any cooling issues though (going by original gauge) but did the mod anyway as mentioned earlier by someone they will fail at some point

There is a massive difference in car between slow and high speed fans switching on, you will know
 
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