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Topic: Aux fan and clutch fan Reply to Thread
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  Topic Review (Newest First)
07-03-2013 03:32 AM
Darryl Elkins I did not replace the magnet but clean it and the connections. There is 12 volts at the temp sensor. Haven't checked at the magnet. Kinda hard to get at now.
06-30-2013 02:16 PM
Jippi im confused, did u replace the magnet in the end? if i got you right even with the new fan and such it still doesnt work?? you need to be careful on here people are using different year cars for examples i see pics of 87s and 84s and its all different. 83-84 and some early 85s were the same, 85-86 were another type, 87-88 was another and 91-93 was another. the 3 prong sensor is a dual throw switch as you know and switched the em fan and the electric aux fan. the different colors (red, black, and green ) i believe are different temp settings. with everything else connected unplug the clutch fan at the clutch, using a multi meter (not a test light) test to see if there are 12 volts at the connector, when you test make sure the car is at operating temp.
06-30-2013 11:36 AM
Darryl Elkins
Update

After rebuilding the head complete with replacing the water pump. Once everything was put back in place I tested the clutch fan circuit with a test light and the test light laminates on but the magnet does not engage nor does the fuse blow anymore. After all that I wish I had a new magnet sitting on the shelf.
06-04-2013 09:42 PM
Darryl Elkins
Quote:
Originally Posted by zhenya00 View Post
I would not suggest rewiring the fan. Get it to work the way it was designed and you'll be fine. FWIW, you don't have a 110C sensor. You have a 100C sensor (the black 3 prong) that triggers the clutch fan. Your aux fan is triggered by one of two scenarios. 1) when the a/c is turned on and the pressure switch triggers the relay that engages both the aux and clutch fans. This is 'low speed' mode. 2) via the blue temperature sensor when the temp reaches a preset threshold (I believe this is 110C but not sure). Note that the blue device is a sensor rather than a switch as it feeds a voltage to a control unit that decides what to do. So yes, you could probably hook up the aux fan to the black 100C switch rather than the clutch, but then you'd only have one fan rather than 2, and it would only run at high speed rather than variable.
Will trouble shoot it this weekend.

[/QUOTE]BTW, where are you headed to in NY?[/QUOTE]

Be in NYC around June 24 til the 26th.
06-04-2013 07:49 PM
zhenya00 I would not suggest rewiring the fan. Get it to work the way it was designed and you'll be fine. FWIW, you don't have a 110C sensor. You have a 100C sensor (the black 3 prong) that triggers the clutch fan. Your aux fan is triggered by one of two scenarios. 1) when the a/c is turned on and the pressure switch triggers the relay that engages both the aux and clutch fans. This is 'low speed' mode. 2) via the blue temperature sensor when the temp reaches a preset threshold (I believe this is 110C but not sure). Note that the blue device is a sensor rather than a switch as it feeds a voltage to a control unit that decides what to do. So yes, you could probably hook up the aux fan to the black 100C switch rather than the clutch, but then you'd only have one fan rather than 2, and it would only run at high speed rather than variable.

BTW, where are you headed to in NY?
06-04-2013 07:44 PM
holmesuser01
Quote:
Originally Posted by Darryl Elkins View Post
This weekend the front brakes and rotors will be replaced so if there is time I may dig into the problem. It looks like I will need a new sensor switch for that and I may plug the AC fan to the clutch fan so that it starts at 100 instead of 110. It is going to be warm on our cross country trip. Oregon to NY and back...its going to be a blast!
You need to troubleshoot first. If your electromagnet on the fan clutch is shorted out, you will instantly blow out the temperature switch.
06-04-2013 07:16 PM
Darryl Elkins This weekend the front brakes and rotors will be replaced so if there is time I may dig into the problem. It looks like I will need a new sensor switch for that and I may plug the AC fan to the clutch fan so that it starts at 100 instead of 110. It is going to be warm on our cross country trip. Oregon to NY and back...its going to be a blast!
06-04-2013 10:18 AM
zhenya00 I would not suggest swapping the fan magnet until you identify what is causing the fuse to blow. It may be in that part, but it's just as likely to be in the wiring and if that's the case changing the magnet won't do any good.

Ok, fuse is correct amperage, just checking...
06-04-2013 10:06 AM
Darryl Elkins The fuse that is blowing is white (8).

A new sensor switch and clutch fan magnet is about 100.00 with expedited shipping. I may just swap them out. I don't want any over heat issues with my road trip that starts on the 13th.
06-04-2013 10:02 AM
zhenya00 Not sure what you mean by 'move the clutch fan plug to the a/c plug?

As a work-around, you can jumper the aux fan to run all the time, but it will be loud.

You can test the a/c side of the circuit (short of the high pressure switch itself) by jumpering the connector at the high pressure switch and seeing what happens.

To test the fan clutch circuit, disconnect both ends of the cable (from the sensor and from the clutch, and check for continuity and shorts on both ends. Also check the fan clutch for a short to the clutch body itself with the wires disconnected.

What rating fuse is blowing and what position is it in the box? (It should be fuse #1)
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