Jason_86_951

I've swapped relays, checked fuse, and both are ok. I've been looking at the wiring schematics and it looks like the temp sensor has two contacts to turn on #1 or both. The relay also has an input from the heating control switch, which I IIRC turns on both fans.

So at this point it has to be in the wiring to the fan or the fan itself.
Has anyone had a fan fail?
This weekend I will jack the car up and get to the fans contacts and check for voltage.
Am I missing something stupid?

Thanks in advance,
Jason

Jeremy Himsel

Switch the plugs temporarily and see if the fan kicks on.

hosrom_951

Aren't there resistors on the fans? at least that is what i read, maybe one is bad?

But yes, try switching plugs and see what happens.

Waterguy

The fan wiring near the resistors was overheated and in very bad shape on mine; you might check there. The resistors are located to the right (passenger side) of the heater fan blower under the plastic cowling at the base of the windshield.

Jason_86_951

Hey I've even got a spare one of those.
I'll try that first. If that doesn't do it I'll remove the belly pan and swap plugs.
Thanks,
Jason

hosrom_951

What colour(s) are the resistors? i want to check mine as well.

There are two blue 'things' on the top of each side of the blowers (aren't those the microswitches or something)?

Sorry for asking so much just want to check mine out

Jason_86_951

Well I swapped out the resister pack...no change. doh!
I'll try tomorrow to measure voltage at the plug on the fan and report back.

It's never something simple is it?

hosrom_951

Jason: Do you have a pic of where it is? does it sit on top of the vacuum controller on the blower motor?

Jason_86_951

It sit on the blower, under the cowl. It's white about 1/2" wide by about 4" long with a black wiring connecter on top of it. It's secured by 2 screws into the blower case.
Jason

hosrom_951

Oh THAT one man......i got to wake up thanks!

Red1

It's probably the fan. Try to spin it and see if there's any resistance. I just replaced one a couple months ago that was practically siezed up.

Waterguy

Sorry, Jason, I should have been more descriptive. The cooling fan resistors are located further to the right (passenger side), and look like two large (2-3 inch?) white ceramic donuts, not the resistor pack on top of the heater blower. The problem I had was with heat damage to the heavy red wires going to the resistors. If you get a break in those wires, the fan would run on high speed (when the A/C switch is turned on) but not on low speed.

alengyel

Don, do you access them by removing the glove box and they are mounted on the underside of the battery tray?

Waterguy

On an 89 951, you access them under the hood, by removing the black plastic cowling between the base of the windshield and the firewall. I assumed that it was the same on all 85.5+ 944s, but Clarks Garage refers to them as being in the location you described. Given the size of them and the amount of heat they generate (0.9 ohm resistors, after all), it makes more sense to mount them where there is some air flow.

alengyel

Given your description of the resistors, my 86' has them located under the battery tray. I have one of the lower votage wires broken off the small round thing next to the bigger round white ceramic resistor.