Cooling Fan problem 1990 CQ

[CQ2226]

The cooling fan on my 1990 Coupe Quattro 20v isn't cutting in as it should. We have changed relays and checked circuits etc. We changed the temp sensor from 95 degree down to an 85 degree but still no good. When the car idles and temp rises the warning light comes on, still no fan. The fan only cuts in when the car is switched off immediately after the warning light comes on, won't cut in when car is running.

Any ideas lads?

[msh]

So, what happens when you short pins of fan switch connector? And how much do you heat it up that warning light lits up?

[CQ2226]

When the switch is crossed the fan cuts in every time no problem so to me the switch and wiring seems ok. The temp warning light comes on just above 3/4 on the gauge. I can get the exact temp later on if it helps.

[John.]

Originally Posted by CQ2226

We changed the (1)temp sensor from 95 degree down to an 85

Originally Posted by CQ2226

When the (2)switch is crossed the fan cuts in every time no problem so to me the switch and wiring seems ok.

Is the above (1) sensor and (2) switch the same thing you're referring to?
The fan switch is at the bottom of the radiator......if the connections are bridged and the fan cuts in then assuming there's coolant behind the switch then it's the switch that's at fault surely?

[CQ2226]

Originally Posted by John.

Is the above (1) sensor and (2) switch the same thing you're referring to?
The fan switch is at the bottom of the radiator......if the connections are bridged and the fan cuts in then assuming there's coolant behind the switch then it's the switch that's at fault surely?

You're right John, it has to be the switch. 1 and 2 yes are the same switch at bottom of radiator. Bottom of radiator gets warm as it should too. It was only when I rang to tell my supplier it may be a dodgy switch he told me there were 3 types. I'll try another type and see how I go. Thanks