Thermo fan switch location

[NormK]

Ok as the title says can anybody point me as to where they fitted the thermo fan switch on a MW Caprice. I have just replaced the radiator that split the top tank and I now think that the thermos did not come on and this caused the problem.
Thanks Norm

 

[Immortality]

Thermo fan is controlled via the PCM.

 

[NormK]

Thanks for that, any idea where the PCM senses it from?

 

[Immortality]

Engine coolant temp sensor. Does the dash show the correct engine temp?

Depending on the age of the vehicle temp may have not been the issue, rather just age of the component. Another issue could be the coolant pressure cap.

 

[NormK]

Thanks again immortality, the radiator was about 2 years old and the car was hardly used for the last 12 months. It appears to show correct temp but that is only a guess. I fitted the new radiator today and had the car running for probably 20 mins to get all the air out of the system and the fans made no attempt to start. When the radiator failed on Sunday, the first thing I looked at was the fans and they were not running, this is why I think there is something wrong. I have tested the fans and they both work so the fans are not the cause. I'm contemplating fitting an adjustable thermo switch sensor in the top hose and just let it work that way. See any objection to that?

 

[Immortality]

Better off figuring out why it's not working as designed. Fan should also come on when turning on AC.

Checked the relays?

 

[NormK]

Pulled the relays out and tried to test them as a normal relay but got no clicking . Not sure if I was testing correctly, not sure if they should click but I assume they should

 

[Immortality]

Swap with another relay that is known to work.

 

[NormK]

With the air con on the fans are working

 

[NormK]

Thanks for your patience immortality where about in Ukland are you situated, my son lives in New Lyne. Anyway this has three relays for the fans marked R17 R19 and R20. Seeing the fans run with the aircon on, I guess I could pull the relays till the fan stops and that would tell me which one does the air con side, then I need to work out what the other 2 do.
Thanks again for your help.