Cadillac Catera and Cimarron Forum Discussion, 2001 Catera ac fan not staying on in Past Cadillac Vehicle Discussion; Hi,
It's been a while since I have been here. Anyways my catera has a new issue, maybe it is ...
It's been a while since I have been here. Anyways my catera has a new issue, maybe it is normal but want to know if anybody had this problem before. Turned on the car today with the AC running and I could hear the AC fan kicking in then turns off. The fan runs for about 2 seconds and shuts down and happened several times. What could be the problem? Also, the temp gauge goes all the way to red once in a while. Could this be related to the AC fan issue?
Retho78, do you have information to test the various fan conditions?
The following should allow you to simulate various activations for fans,
Fan test connector info: Open the engine bay fuse and relay box, and you'll see a 6 pin test connector attached to relay K87 ( count 6 back from front of car ). Pins are numbered 123 left to right, 456 right to left. With pin1 top row left if you look at the connector with the two keys on your left hand side. ( I'll try and post a picture as soon as I've worked out how.. Can't find an upload option ).
My car has 3 fans, two ostensibly for the air conditioning, in front of the air con radiator right at the front, and one behind the engine's radiator.
Pin 1 = coolant temp switch output stage 1 ( quite hot )
Pin 2 = pressure switch output
Pin 3 = +12 ignition on - via fuse 29 on my 3.2 Elite - NOT fuse 15
Pin 4 = coolant temp switch output stage 2 ( very hot )
Pin 5 = coolant temp switch output linked to air con
Pin 6 = earth
So, if you earth the following pins, the folowing happens ( or should )
Pin 1 when earthed, runs both air con fans slowly.
Pin 2 when earthed, runs NS air con fan fast.
Pin 3 +12 V ( Don't earth this !, unless you want to blow a fuse ! )
Pin 4 when earthed, runs radiator fan ( big one behind radiator )
Pin 5 when earthed, runs NS air con fan fast. ( Same as 2, but via a different relay ).
I forgotten where I got this info from but it is not my original and I have not verified it either.
Engine Cooling Fans (A/C Operation): When A/C compressor is turned on, fan control relay K87 is energized and auxiliary engine coolant fans 1 and 2 will operate in low speed. In order to prevent inadmissible high refrigerant pressure in refrigerant circuit, auxiliary engine coolant fans 1 and 2 are switched from low speed to high speed at refrigerant pressures above approximately 275 psi. When pressure drops less than about 217 psi, auxiliary engine coolant fans 1 and 2 are switched back to low speed.