Forcing AC condensor fan to run?
#1
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I've read numerous posts, as well as the DIY on p-car.com ... I know it's possible to force the oil cooler fan to run at hi-speed by unplugging the harness from it, is it possible to do the same to the AC condensor fan? Mine's cycling from off to high-speed and I won't have a chance to have it fixed for a while (AC is cooling fine right now). Resistor is bad, apparently.
Or, can the AC fan be jumpered at the relay to run? I can't tell from the posts whether it will run with the ignition off when it's jumpered; the oil cooler fan does, apparently.
Last night, I got caught in stop and go traffic for a while, oil temps rose to the midpoint on the dial, and after getting free and driving 60 mph for 20 minutes, they never came back down. No idea if that's related to the AC fan, but this morning I forced the oil cooler fan to run high speed and the temps have stayed down.
Any advice?
Vic
95 C4
Or, can the AC fan be jumpered at the relay to run? I can't tell from the posts whether it will run with the ignition off when it's jumpered; the oil cooler fan does, apparently.
Last night, I got caught in stop and go traffic for a while, oil temps rose to the midpoint on the dial, and after getting free and driving 60 mph for 20 minutes, they never came back down. No idea if that's related to the AC fan, but this morning I forced the oil cooler fan to run high speed and the temps have stayed down.
Any advice?
Vic
95 C4
#4
Burning Brakes
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I can't imagine your oil temps are related to your a/c malfunction. If the low speed stage for the oil cooler fan is working, you're OK. Is the exterior of your oil cooler clean and the airflow to it unimpeded? There's really no other way to improve its efficiency except the fan forced to high speed, as you've done. I see it's pretty hot in Boston at the moment, the slow cooling down at highway speeds sounds fairly normal to me.
You could theoretically jumper terminals 3 and 5 in R14 but I think the fan would run even with the ignition off. No good. So you'd have to use one of the unused ignition-switched terminals for the 12 volt side, run a fresh ground - complicated, and potentially risky - I'd say if you're staying cool, just go with the current status and get the first stage (resistor) fixed as soon as practical.
You could theoretically jumper terminals 3 and 5 in R14 but I think the fan would run even with the ignition off. No good. So you'd have to use one of the unused ignition-switched terminals for the 12 volt side, run a fresh ground - complicated, and potentially risky - I'd say if you're staying cool, just go with the current status and get the first stage (resistor) fixed as soon as practical.
#5
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Vic,
You can modify the AC relay in the same fashion as the oil cooler relay mentioned here: https://rennlist.com/forums/showthre...ht=mistake+fan
This will force the fan to run at high speed when the low speed signal is present.
It's a good work-around in your situation.
HTH,
Scott
You can modify the AC relay in the same fashion as the oil cooler relay mentioned here: https://rennlist.com/forums/showthre...ht=mistake+fan
This will force the fan to run at high speed when the low speed signal is present.
It's a good work-around in your situation.
HTH,
Scott
#6
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Thanks, all ...
I left the oil cooler fan running on high today, got stuck in some crawling traffic on the highway in the heat, and the needle never broke the 194 mark. It's quite effective for those summer commutes.
I also swapped relay on the AC and oil cooler and the AC was still not working right, so it's probably the resistor.
Vic
95 C4
I left the oil cooler fan running on high today, got stuck in some crawling traffic on the highway in the heat, and the needle never broke the 194 mark. It's quite effective for those summer commutes.
I also swapped relay on the AC and oil cooler and the AC was still not working right, so it's probably the resistor.
Vic
95 C4
#7
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Took a short piece of 16 gauge wire and jumpered terminals 85 and 85C this morning, AC condensor fan runs on high when the AC is on, doesn't run when it's switched off or the ignition is off. AC cools better, easy 1-minute fix. Thanks ... Rennlist pays off again!
Vic
95 C4
Vic
95 C4