Low Speed Fan Not Working

[allye 530 3 Cars]

Rallye has been running great just a couple little things to sort! I'v got twin on it from a stdt but only the high speed (both fans a same speed) kicks in and only when the temp gauge gets a little on the hot side. This happens standing in traffic, it rises quite quickly actually. All other driving is fine though.

 

Would like to get the low speed fan working as I'm scared of traffic at the moment and try to avoid it!

 

Thanks, Ali

[Anthony 1,003]

With the ignition on, unplug the connector from the thermoswitch and bridge a pair of contacts at a time - one pair should run the fans on slow, and one pair should run them on high-speed. If that works, the thermoswitch is goosed, and if it doesn't, then work backwards from there - replacing the relays would be the next step I should think.

 

IIRC the diesel fan setup is wired to run the fans in series on slow speed, and in parallel on high speed. This is different to how it's done on a GTi, whereby the slow speed fan is run through a resistor and high speed runs direct.

 

Personally, I just do away with the slow speed altogether when I do fan wiring, and just have it come on high speed straight away - a bit of noise doesn't bother me, but keeping the engine cool does.

[allye 530 3 Cars]

I though about trying to get both to come on, on high speed when the low speed should come on as I'm sure most of you know gti6's like to run warm!

 

How would I go about doing that?