Hi everyone.

The cooling fans on my S2 Cab switch on whenever the temperature rises but their operation has become intermittent. i.e. they are running in an on-off-on-off cyle ... stay on for about 5 seconds and then switch off for 2 / 3 seconds ... then on again for 5 secs ... then off again for 2 / 3 secs ...

I had the timing / balance shaft belts adjusted last week and noticed this about the fans since then. Before the belt re-tensioning job, the fans did not operate like this (i.e. on-off-on-off cycles ...).

Of course I'll take the car back to the mech in the next couple of days, but any help from this forum would be great.

Thanks & regards,

Rehan

 

I can't see the belt job affecting anything,
but you can check for loose cable or something, on the electrics concerning the fan motors, thermostat sensors etc

 

Is it a 1989? I have heard this is more common on that year.
I had this problem and a friend told me to look at the resistor near the windshield by the battery. I think the PN is 944 616 521 00 although it may have changed on the S2.
That was not my problem, but the wiring to that resistor was.

 

I have a 1989 944S2 and had the same problem occur on my car. After a lot of searching, it was determined that there was a short / corrosion on one of the wires going to the fan switch sensor.

Basically, the sensor was mistakenly thinking that fan A wasn't working, and caused fan B to turn on. Once fan B came on, it sensed that the temperature was low enough and cycled off. Then the original sensor again thought fan A wasn't working, and would cause fan B to turn back on....and so on.

If you wish, I can have my shop give you the details - just PM me.

Good luck!
-Z-man.

 

Pull the plug on the thermoswitch (the switch on the radiator) and clean it out, plug it back in and see what happenes, that fixed mine

 

It's corrosion on the connections at the big white (beige now) resistors at the windshield. My car actually burned the wires from an intermittent short for about 1/4" from the resistor connections. I clipped off the burned part of the wire, then crimped and soldered (and taped) new connections on. Problem solved.

Good luck!

Dal.