Oil cooler fan operation question
#1
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Thread Starter
Oil cooler fan operation question
So after replacing my cooler, the car is running significantly colder oil temps (yay), but I replaced the fan at the same time with one from Autobahn. I have yet to see the fan work, even with the oil temps at 9 o’clock. I’ve tried engaging the AC that isn’t there, and the fan does not come on. Is it a given that with the AC on, the fan should at least come on low speed? I’m wondering if doing the oil cooler ballast at the same time if something went wrong. I’ve doubled checked the cooler fan harness is fully seated, though I haven’t been able to double check the ballast harness. I’m 95% sure it’s fully seated, but without pulling the bumper off again, I can’t 100% confirm.
Any thoughts on how to verify the fan is actually working before I slap the wheel well liner back on?
Any thoughts on how to verify the fan is actually working before I slap the wheel well liner back on?
#2
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Thread Starter
Hmm let it idle long enough and the fan eventually came on, but it appears to be at high speed. Wasn’t paying close enough attention to see if it came on low speed first. When I checked the oil temp was hovering around 9:30-9:45ish. Not sure around what temp low speed is engaged though?
#3
Rennlist Member
is your resister good? AC won't change anything IIRC, that will activate the fan on the driver side (that you don't have?)
Its coming on about the right time thought, which is ~10 o'clock. which is too high for me. I modded with a resister in parallel to the sensor and it comes on right at 9. With the secondary cooler I have the car runs about 2 needles below the first line (about 180) all the time now.
Its coming on about the right time thought, which is ~10 o'clock. which is too high for me. I modded with a resister in parallel to the sensor and it comes on right at 9. With the secondary cooler I have the car runs about 2 needles below the first line (about 180) all the time now.
#5
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Thread Starter
is your resister good? AC won't change anything IIRC, that will activate the fan on the driver side (that you don't have?)
Its coming on about the right time thought, which is ~10 o'clock. which is too high for me. I modded with a resister in parallel to the sensor and it comes on right at 9. With the secondary cooler I have the car runs about 2 needles below the first line (about 180) all the time now.
Its coming on about the right time thought, which is ~10 o'clock. which is too high for me. I modded with a resister in parallel to the sensor and it comes on right at 9. With the secondary cooler I have the car runs about 2 needles below the first line (about 180) all the time now.
Which resistor specifically? The ballast resistor on that side? I just put a new one in when I replaced the cooler. If it's coming on at the right temp I'm not too worried about it. The condenser/dryer/whatever is wedged into the left front is still there, however the compressor is not. That fan I did confirm comes on with the AC button engaged, but it wasn't activating the oil cooler fan which I mistakenly thought it did.
#6
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#7
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From P-car https://p-car.com/diy/fan/
To verify that the fan will physically operate in slow or fast speed:
-Remove relay R04 (oil cooler blower).
-Jump terminals 3(30) and 7(87c) for slow speed. Fan should run, even with the ignition off. If the fan runs in slow speed, your ballast resistor should be okay.
-Jump terminals 3(30) and 5(87) for fast speed. Fan should run, even with the ignition off.
You can check the A/C condenser fan similarly, removing relay R14.
-Remove relay R04 (oil cooler blower).
-Jump terminals 3(30) and 7(87c) for slow speed. Fan should run, even with the ignition off. If the fan runs in slow speed, your ballast resistor should be okay.
-Jump terminals 3(30) and 5(87) for fast speed. Fan should run, even with the ignition off.
You can check the A/C condenser fan similarly, removing relay R14.
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#8
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Thread Starter
+1. This is what I did to make sure my fan was working properly, easy to check low and high speed functionality. I also tested the relay while it was out to make sure it was not faulty.
From P-car https://p-car.com/diy/fan/
From P-car https://p-car.com/diy/fan/
That's awesome detail, thank you.
#9
Rennlist Member
FWIW, you can also unplug the temp sensor at the oil cooler and attach a potentiometer, ie a variable resistor, and slowly turn to simulate the temp sensor. Fan should come on slow and fast depending on resistor value. It worked for me.
#10
You can just unplug the temp and it will run on high when ever the car is on
#11
It’s my understanding that the ballist resistor just controls the low speed fan operation that, as others have mentioned, should engage at the 9oclock position.
First step is to jumper the relay for both slow and fast speed. I had a bad temp sensor. There are a lot of if and thens to figuring out what needs to be replaced, but Tores site is very comprehensive and walks you through each step eliminating everything along the way so you know exactly what needs to be fixed.
The way Porsche used the CCU to control all of this is a nightmare and hopefully that doesn’t end up being your problem...but, there are a few places that repair them.
#12
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Thread Starter
Installing a manual override switch does the same thing as it just breaks the circuit and once the CCU doesn’t see the temp sensor it goes into fast speed mode. I chose to do this as I like to be able to control the oil cooler fan myself.
It’s my understanding that the ballist resistor just controls the low speed fan operation that, as others have mentioned, should engage at the 9oclock position.
First step is to jumper the relay for both slow and fast speed. I had a bad temp sensor. There are a lot of if and thens to figuring out what needs to be replaced, but Tores site is very comprehensive and walks you through each step eliminating everything along the way so you know exactly what needs to be fixed.
The way Porsche used the CCU to control all of this is a nightmare and hopefully that doesn’t end up being your problem...but, there are a few places that repair them.
It’s my understanding that the ballist resistor just controls the low speed fan operation that, as others have mentioned, should engage at the 9oclock position.
First step is to jumper the relay for both slow and fast speed. I had a bad temp sensor. There are a lot of if and thens to figuring out what needs to be replaced, but Tores site is very comprehensive and walks you through each step eliminating everything along the way so you know exactly what needs to be fixed.
The way Porsche used the CCU to control all of this is a nightmare and hopefully that doesn’t end up being your problem...but, there are a few places that repair them.
Good to know. While it was apart I replaced the cooler temp sensor, and ballast resistor. Sounds like I should jump the relay to confirm the low speed, and then go from there.