Cooling Fan Not Working!

[mikeygulley 19 1 Cars]

Hi Guys and Gal's!

 

My father has a problem with the cooling fan not coming on in his Gentry turbo.

 

It has the blue 3 pin connector and we replaced it with a new one a few days ago. The wiring for the fan is much more involved than my GTI, its located in a black box behind the pass headlight. There are 2 relays? in there and plenty of wires. I tested the fan but the only way I could run the slow and fast was to disconnect the plug on the thermo switch turn the ignition to the second click then link them out on the plug.

 

Both speeds worked so assumed it was the switch, but after replacing it the fans still don't come on!

 

My father insists its my fault because it has only done it since I wired in a spiky rev counter loom, but I never connected it tot he multiplug in the end!!

 

Is there something a miss here, particularly with the way I had to test the fan motor???

 

I will take the thermo switch out and test it in hot water, my worry is that does the ignition have to be on for the fan to work!!!???

 

 

Thanks in advance,

 

Mike

[Anthony 1,002]

On the relay controlled twin fan setup, the ignition does need to be on. There should be three relays in total.

 

If you disconnect the 3 pin blue plug and manually bridging the contacts makes the fans run, then logically, it must be the thermoswitch that's at fault IMO. If it was a wiring, relay, or fan issue, then the fans wouldn't run with the contacts inside the 3 pin plug manually bridged.

 

As you're probably aware, the twin fan setup works differently to the single fan setup (as found on non-AC GTi's etc). Both fans will run on both slow and high speed settings, the only difference being how they run electrically - on slow speed, they are effectively wired in series, whereas on high speed, they are effectively wired in parralel.

 

On the 3 pin connector for the thermoswitch, one pin is common, which bridged to one will cause the fans to run slow, and bridged to the other will cause the fans to on high speed. I can't remember off the top of my head which pin is which though I'm afraid.

[mikeygulley 19 1 Cars]

Bridging the pins on the connector is exactly what I did but as said the ignition had to be on for anything to happen.

 

I think I understand the wiring and if the fan is working when I bridge the connectors then I agree it must be the thermo switch. My father replaced it but the car has chucked its water out twice since!! He didn't let her run up to temp to check it though!

 

I have a feeling it could be something else but I will dip the thermo switch in hot water this evening to eliminate it.