How To Make Fans Come On At Low Speed

[allye 530 3 Cars]

Hi all,

 

Rallye is running great with only a couple teething problems. One being it likes to run a little hot at stand still, to the point I avoid traffic, turn the heaters on and even turn it off!

 

It's got twin fans from a d turbo and standard gti rad. Low speed fan does not come on onlyu the high speed fans at a high temp, I would like to be able to get both fans to come on at high speed on the lower temp setting, if you get me!? - is that possible? At current they only come on as the needle is only one bar from the red!

 

Cheers, ali

[kyepan 291]

not completely sure about tu looms, but the gti has a spare plug, joining pins 1-2 or 1-3 will test the low and high speed circuits, if not, try another fan resistor.

 

cheers

 

j

[welshpug 1,666]

the TD had a relay setup to switch the fans as well as the thermoswitch, did you gt this with the fan cowling? should just be a case of plugging it in.

 

For low speed they run in series and high in parralel.

[petert 601]

If only high works it's possible the sensor is faulty. Pull off the plug and try shorting out pairs as kyepan suggested with a paper clip, etc. If it's the old style sensor with spade connectors, the odd terminal is common. The two pointing the same way are high and low respectively.

[dino20vt 3]

the TD had a relay setup to switch the fans as well as the thermoswitch, did you gt this with the fan cowling? should just be a case of plugging it in.

 

For low speed they run in series and high in parralel.

 

Do turbo and n/a diesels have the same twin fan and relay setup?

Edited August 22, 2011 by dino20vt

[welshpug 1,666]

nope, n-a has the same setup as a gti, different temp fan switch though iirc

[Anthony 1,003]

nope, n-a has the same setup as a gti, different temp fan switch though iirc

205 NA Diesels that I've seen have all had the relay setup and twin fans

[welshpug 1,666]

my mistake, not worked on many as they're genrally quite reliable compared to the petrol variants I know the rad is the same as the gti (i.e thinner than the TD)

[Paul_13 212 1 Cars]

Yep twin fan from experience

[dino20vt 3]

205 NA Diesels that I've seen have all had the relay setup and twin fans

 

Do their fan switches contacts go from | __ | to - - - (or are they single speed)? like the GTI's did when the phase 2 came out? I ask as i very quickly popped the bonnet of a very late diesel in a scrappy, pretty sure it had twin fans, sure'ish it had an early switch even though it was a L or M plate?

[Paul_13 212 1 Cars]

Its a blue plug with terminals - - - on my j reg diesel

[pug_ham 245 3 Cars]

205 n/a diesels still have the two speed fans & a twin fan set up.

 

The difference in the fan switch is simply down to age, I suspect you could find two 205 n/a diesel's from the same year, one with the |_| plug & the other with the --- type.

 

I think they changed around 1989 to the blue plug --- type.

 

g

[allye 530 3 Cars]

Many thanks gents. It's a blue switch the rad, it's got a complete gti loom and stdt fan set up, looking back I think I May be missing a part of the low speed sensor setup.

 

so is it possible toget both fans to come on at the low speed switch?

[welshpug 1,666]

yup, you need the diesel fan loom.

[Anthony 1,003]

From memory, on the diesel fan setup, both fans run in series at low speed, and in parallel at high speed.

 

Unplug the radiator thermoswitch and short the pins using a length of wire - two should run the fans on slow, and two should run it on high speed. If that works, then the thermoswitch is goosed, and if it doesn't, it's probably one of the relays that control the fans that's not working properly or a broken wire somewhere.

[Rob_the_Sparky 10]

From memory, on the diesel fan setup, both fans run in series at low speed, and in parallel at high speed.

 

Unplug the radiator thermoswitch and short the pins using a length of wire - two should run the fans on slow, and two should run it on high speed. If that works, then the thermoswitch is goosed, and if it doesn't, it's probably one of the relays that control the fans that's not working properly or a broken wire somewhere.

 

Your memory is good