85 coolant fan not working???????
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From: Chicago Burbs, IL
St. Jude Donor '03 & '06
85 coolant fan not working???????
The fan works, gave it 12 volt power and worked no problem. The temperature gauge in the car works fine, I can see it climb when we're at a stoplight and the damn fan doesn't kick on. Is this a fan relay? If so, where is it located? Can't find a traditional relay box under the hood and no relays in the fuse box. Help is greatly appreciated.
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From: Summerland B.C. Canada
Thread Starter
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From: Chicago Burbs, IL
St. Jude Donor '03 & '06
Originally Posted by AGENT 86
Instructor
Joined: Nov 2003
Posts: 126
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From: Belmont MI
Check the orange wire from the battery to the relay that runs under the master cylinder. Mine got corroded and caused the situation that you describe. Its possible that all you need to do is splice and solder a wire and put some shrink over it. I was able to put 12v to the fan and get it to run also before I did this.
I did mine in .5 can of beer.
I did mine in .5 can of beer.
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Melting Slicks
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From: Reno/Sparks Nevada
Jumpering the 2 thicker wires at the relay bypasses the relay and will also check the power to the relay and continuity/power to the fan. What is also typical in these older relays is the connector at the relay is intermittent or open due to distortion/heat. Sometimes the wiring gets old and corrodes or loses relay contact from the heat of the engine or from the relay. Make sure the wires are pushed all the way into the relay, then test it while driving too. See if it comes on. Ecklers sells a relay upgrade kit which uses the new relay and connector. They also sell a relay connector kit which splices into your existing wiring to replace your existing plug. Don't thow money at the car, Agent86s link to the troubleshooting pages right out of the Factory Service Manual (FSM) is the best place to start. Ground the green/white wire terminal to see if the relay works and turns on the fan. Check the big orange wire for 12 volts. Check the big black/red wire for continuity between the relay connector and the fan. The little blue? wire goes to the fuse when the key is on. Check for 12 volts there too. I'm gong off memory on these tests but I think they're right. Someone else will probably chime in.
Art
Art
Last edited by MrRenoman; Jun 11, 2005 at 12:03 PM.
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From: Chicago Burbs, IL
St. Jude Donor '03 & '06
Update...New relay installed and it still doesn't work. I'm going to have to start with the flowchart on Monday. Grounded the relay and it worked fine but the fan didn't come on. Power is going in to the relay though. I used a jumper to the fan and it worked. The fan had some rocks buried inside the shroud holding it from turning at one point. I cleared all that out and the fan works but I'm clueless at this point. I thought it may be the temperature control sensor but the dash temperature reads just fine. Related?
Drifting
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From: GA
Originally Posted by doo600
I thought it may be the temperature control sensor but the dash temperature reads just fine. Related?
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From: Chicago Burbs, IL
St. Jude Donor '03 & '06
Originally Posted by Morley
They are not the same. The gauge gets its temp readings from the temp sender in the cylinder head. The ECM (which turns the fan on and off) gets its temp readings from the coolant temp sensor mounted in the front of the intake manifold.
Last edited by Doo; Jun 12, 2005 at 06:01 PM.
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From: The Top of Utah
Originally Posted by madride
Check the coolan6t fan temp switch, its in the right cyl. head behind the dipstick
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Team Owner
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From: Cincinnati, Oh USA
The main fan relay gets power from the battery through a fusible link on the jump start bolt behind the battery (there are 8 wires on this bolt). Check for 12v on the large red wire on the fan relay. Your fusible link may be blown.
Intermediate
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From: Cedartown Georgia
Can the fan motor go bad even if it still spins by hand? Cause my fan was working now it's not even when my car gets up to 242 degrees.
