HELP: Auxiliary fan not working. A/C works intermittently
My a/c blows intermitently cold/air temp. Seemingly working sometimes and other times not. Which prompted me to recharge the freon (r-134a).
While doing so, I noticed the compressor stopped. First off, is this normal? Is it normal for the compressor to stop on it's own (and I'm assuming it starts on it's own too)
I also noticed my auxiliary fan not working. (Which sent a lightbulb off in my head about why my car sometimes overheats at stop lights or bumper to bumper traffic).
So anyway... I grab my bentley manual, and I'm still STUMPED!
If I jump the black/green wire to the ground (Brown wire) with the ignition ON, I get nothing. The fan does not move. It doesn't move in high speed either (jumping black/gray to brown). Nothing happens with the fan, however, the weird thing is... I hear the relay click. The manual doesn't say anything about it, but if I hook a test light up to the terminals 30 & 86 of the relay socket, the light goes ON when I jump the wires at the temperature switch... make sense?
So... the fan does not run when powered directly by jumping the connectors @ the temperature switch.
It does not run when the a/c is on, or when the engine is warm enough to where it's suppose to. So basically, it never runs.
All fuses are fine, none are blown.
The bentley manual states "On early production cars (up to 9/92): If fan operates only on high speed and no electrical faults have been found up to this point, use an ohmmeter to check that fan resistor is not electrically open". My car is a '93, would this apply to me?
I also found two mystery harnesses that someone (before me!) tucked into the bumper shrowd near the bottom, driver's side of the aux. fan/radiator. LOok at the picture attached, and see if you can help me identify them! Maybe they are part of my problem!
THANK YOU ALL FOR YOUR HELP! I hope we can get this thing fixed soon!
In addition to what you have done, check to see if 12V is getting to the fan. I read here that the fans are a rather common failure item. I don't know about the other connectors. Could have been for anything if someone added it.
If there is no power in the harness to the fan, I would guess that there is a break in the wiring based on the other testing you've done. Trace the harness and fix it or bypass it. You could also apply 12V to the fan itself to make sure it works. You should be careful, as the current draw is substantial.
Oh, and yes, the compressor does cycle on and off.
the yellow sensor, is a temp sensor for your interior obc display.
the other wires can be for fog lights, i dont know if you have them installed or not.
But i have never seem that..
About the fan, i do want to bring to youre attention that there is a pressure swicth located on top of the dryer canister on the ac system. This is a silver canister next to the radiator. this swicth has four wires, that control the fan and ac compressor.
most of the time the connections get rusted and so contact is lost.
i recommend you check the swicht connections.
keep in mind the swcith itself could be bad. replacement requires discharge of the ac system.
hope this helps.
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