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Cooling fan relay location for 1985? Fan test?

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Old 05-31-2014, 03:35 PM
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Captainpegs07
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Default Cooling fan relay location for 1985? Fan test?

I just installed a high flow 180F thermostat. I got a new switch from corvette central but my FSM is on order and I won't have it until mid next week. Can anyone show me a pic or a thread with a pic of where the cooling fan relay is?

What is the color of the primary signal and the secondary signal wires for the 1985? I'm going to wire both fans to come on.

Is there a test to make sure the cooling fan itself works?

Thanks everyone!
Old 06-01-2014, 01:10 AM
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Cliff Harris
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The cooling fan relay is located on the driver's side wheel well under the brake master cylinder:



I don't know about wire colors for your year.

The usual way to test a fan is to apply 12 volts to it directly from the battery.
Old 06-01-2014, 03:01 AM
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gerardvg
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Originally Posted by Captainpegs07
I just installed a high flow 180F thermostat. I got a new switch from corvette central but my FSM is on order and I won't have it until mid next week. Can anyone show me a pic or a thread with a pic of where the cooling fan relay is?

What is the color of the primary signal and the secondary signal wires for the 1985? I'm going to wire both fans to come on.

Is there a test to make sure the cooling fan itself works?

Thanks everyone!
Hi
I have an adjustable t/stat, is easy to run a ground to one contact on the switch and the other contact run that to the green wire with white stripe. I joined it there so the ecm can still run the cooling fan when a/c is running. ( the ecm grounds the green wire with white stripe to run the cooling fan)

You can also run the cooling fan by disconnecting the small plug on the a/c fan request switch pipe running to the evaporator, it is next to the high pressure lock out safety switch with two spade terminals unplug it and your cooling fan will run as the ecm sees an open circuit a fan request with ignition on.

See the 85 cooling fans diagram below.


Last edited by gerardvg; 06-01-2014 at 03:10 AM.
Old 06-01-2014, 10:56 AM
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playsdixie
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ground a and b on your aldl...that forces the fans on..
turning the a/c on starts the fan.... you can get a double switch at any hardware strore...ground it and run a wire off each side to the green wire off the fan relay and aux fan relay..then you can turn one or both on....my 85 stays around 180 in s florida with that t stat and set up...
Old 06-02-2014, 07:33 AM
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Captainpegs07
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Thanks very much for the quick and detailed replies! I will look at this and try to get my new switch installed after work!

Old 04-22-2016, 12:56 PM
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reno1985
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Originally Posted by playsdixie
ground a and b on your aldl...that forces the fans on..
turning the a/c on starts the fan.... you can get a double switch at any hardware strore...ground it and run a wire off each side to the green wire off the fan relay and aux fan relay..then you can turn one or both on....my 85 stays around 180 in s florida with that t stat and set up...
hello I have an 85 that I'm running carb so the ecm is not being used. where is tbe secondary fan relay located?
did you just splice the radiator and secondary fans together?
Old 04-23-2016, 08:15 AM
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WVZR-1
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Originally Posted by reno1985
hello I have an 85 that I'm running carb so the ecm is not being used. where is tbe secondary fan relay located?
did you just splice the radiator and secondary fans together?
The wiring diagram in an above post is correct. Modify as you wish. If the under-hood arrangement is "unmodified" then this is the cooling fan relay arrangement.

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Old 04-26-2016, 10:38 AM
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whalepirot
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Haing messed with plenty of the wiring, I am not a fan(arrgh) of manausl switches and the extra wiring, as the complications cause their own problems; this on a properly operating control system. As mentioned, turning on the A/C sahould start fan(s); simple.

Originally Posted by reno1985
hello I have an 85 that I'm running carb so the ecm is not being used. where is tbe secondary fan relay located?
did you just splice the radiator and secondary fans together?
Your '85 may not have a secondary fan and may ground the relay lug via a thermal switch in the right head; no ECM switching involved.

Last edited by whalepirot; 04-26-2016 at 10:41 AM.

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