Radiator Cooling Fan

1984 Mk1 Cabriolet GTI 1.8

Engine temp is fine when driving, no loss of coolant

When stopped the water is discharged from the expansion  tank.

Radiator fan is NOT running.

My question is

Is the radiator cooling fan 2 speed or single speed?

I am assuming the fault may be with the temp sensor fitted to the radiator (2 wires)

I have been told to test just short out the two wires to confirm if the fan is working or not, just need confirmation rather than cause damage to the circuit.

Thanks

Angus

As you have been told, simply bridge the two terminals on the radiator temp sensor to check whether it is working.

Do you have a/c?
Yes then does your fan and Fan switch on the radiator have 3 pins.  Yes then you have a 2 speed fan.

No,

Then you have a single speed fan and it is simple.

Pull the connector off the Fan Motor.
Jumper one of the pins straight to the battery, and the other to ground.  If the fan kicks on then it isn't your Fan, it is usually the Radiator Fan switch.

The Oldie Golfs had a very simple circuit.
Battery inline fuse to the Radiator fan switch left side, power to the Radiator fan out of the switch to the motor.  The other pin on the motor was ground (Frame).


Here are the Caveats.
Your Radiator Fan Switch should be rated the same. as your Thermo-stat.  ie 80C Thermostat then a 80C thermo switch.ycle

Normal Highway Driving (all the Radiator covers on, should hardly ever exceed halfway tp a little right of the Red light in the Temp gauge.  When you stop then the temp may spike and the radiator fan may come on.

Stop and go City Driving you may see the fan turn on of off more often.

If you leave your car in the Parking lot (oldy, as my 81 Diesel did this, that the Fan switch may cycle as the OAT (Outside Air Temp) can cause the radiator to exceed the rated value and turn on the radiator fan.  

After Stopping on a highway drive the Radiator may come on after shutting the car down and run for about 15 minutes.