Position of the thermo switch that operates the air contioner cut out relay.

[mudnut]

G'day all. I am trying to add to he RB30 facts and figures thread. I own a Q with a manual gearbox.

The workshop manual shows that a vehicle fitted with an auto trans has a thermo switch which controls an air conditioner cut out relay.

Am I correct in guessing that the thermo switch is mounted on the transmission and is there to disable the a/c if the transmission over heats?

[threedogs]

what about its there to increase revs when air con is on ??? maybe ?

[mudnut]

On a manual the Fast Idle Control (FICD) is directly operated by the air con relay this operates an actuator on the carby. But on an auto there is an air con cut out relay in series with the air con relay. This second relay is operated by a thermo switch, which is what I am asking about.

[mudnut]

I have found the thermo switch in the workshop manual. It is on the radiator, connector 171M.

This switch operates at 107 degrees C and cuts out the air conditioner. It opens at 103 degrees C, so the air con can run.

[the evil twin]

Yep, there is one for exactly that purpose on the TB42 EFI radiators as well.
Not sure about the TD42 Autos but I reckon 99% certain they would also be the same

[the evil twin]

Sorry... Double post... dunno how that happened?

[mudnut]

From what I could gather from the picture of the TD42 thermo switch it is on the opposite side.

[the evil twin]

From what I could gather from the picture of the TD42 thermo switch it is on the opposite side.

Quite likely, mate

That sensor serves the same purpose on all models IE high coolant temp prevents operation of the A/C so there is less load on the engine and also cooler air to the Rad

[mudnut]

It also makes sense that they have only fitted it to autos as their fluid is also cooled via the radiator.