1997 Olds Cutlass Supreme SL radiator cooling fan relay/controller loation


Yes I searched the archives but no joy :frowning:

I have purchased the new replay and have removed the bracing and cover from the box that houses the various fuses and relays on the front passenger side only to be confronted with 3 identical relays.

1 is labeled “ing syst” so that’s not it. One is labeled “fan cont #2” and the other is labeled “fan cont #1”. Which one is the relay for the radiator cooling fans?

Help it’s 107 here right now and I like to run the AC.


– Muttmike

Thanks a lot slackers! :slight_smile:
The answer to my question (and thank you Mr Goodwrench parts guy for telling me that the relay controlled both fans! NOT!) the that the left most relay (fan cont #2) controls the pass side fans and the right most the drivers side.
So I tested both the relays and they work! :frowning:
The Temp. gauge in/on the dash also works…
So there must be a separate sensor that kicks on the fans.
Does anyone know where the sensor that activates the relays lurks?
Much obliged
– Muttmike

What’re your symptoms exactly? If the AC is charged and the compressor is working, one of the fans should come on when you run the A/C. The other one, however, is strictly thermally-controlled and will only come on if the coolant gets extremely hot. On these larger-engined GM cars, the engine doesn’t really have to work very hard and the rest of the cooling system works so well that the electric cooling fans practically never come on. During the 100,000 miles I drove my old 88 Century, I had the fan come on exactly once, climbing up a pass in Death Valley in the middle of August.

Some GM cooling fans are just activated by the computer based on the input from the coolant temp sensor (typcially located near the thermostat), but others have a separate temperature switch in the radiator itself. A good service manual with a wiring diagram should be able to tell you if you have a separate temp switch in the radiator.