306 coolant fan control - advice please ?

Nigel,

So far I've been able to compare the resistances of the 3 wire sensor to a
similar car, and they look very similar at approx 10C and 70C.
I tried to test the other sensor (which has only one wire!) with a view to
comparing it but couldn't work out quite how to get the connector off
without breaking it.. Duh!
Hopefully I will be able to do some more tests at the weekend.

- Steve

 

I think it's a "Bosch" type, held on with a wire clip on three sides.
Push in the long side and the other two sides will unlock and you can
pull the connector off.

 

Still there ? good...
I've managed to unplug the second sensor, It has a purple ring on it and one
wire going to it.
It stays open circuit at 10C or 70C so I'm presuming that it's only a
thermostatic switch to send to the STOP light ?
Either that, or it's something else, and knackered <G>

Next step ? Not sure, maybe get a dealer to interrogate the ECU to tell us
what the ECU thinks the coolant temperature is ?

Cheers,

- Steve

 

I think you have probably gone as far as you can. You do need to get
it on the Diag and see what the various readings are and whether there
are any faults recorded. If and when you get this resolved, get an ECU
download.