85 radiator fan problems
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Joined: Oct 2004
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85 radiator fan problems
I am having troubles with the cooling fans on my 85. I have both a pusher and a puller fan. Neither will turn on when the car gets hot. I replaced all the coolant switches on the motor.
I was going through the diagnostic section in my Haynes book and it said to jump terminals A and D on the relay harness. The problem is, my harness does not have a terminal D. Nor does my relay. If I jump terminals A and E, the fan runs. Any ideas what to do next?
Also, my book mentioned if there is an auxilliary pusher fan, there is another relay mounted on the shroud. My car does not have this relay.
Help please
I was going through the diagnostic section in my Haynes book and it said to jump terminals A and D on the relay harness. The problem is, my harness does not have a terminal D. Nor does my relay. If I jump terminals A and E, the fan runs. Any ideas what to do next?
Also, my book mentioned if there is an auxilliary pusher fan, there is another relay mounted on the shroud. My car does not have this relay.
Help please
Intermediate
Joined: Apr 2003
Posts: 35
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From: Crestview FL
You should be jumping points A and B on the ALDL connector under the dash. Jumpered and key on will cause the main fan to turn on.
As far as the smaller fan mounted in front of the radiator you should be able to force it on by having the car running with the A/C set to max.
You said you replaced all the coolant sensors and switches but a quick test of the switch located on the passenger side head between cylinders 6 and 8 will determine if the switch is your problem. Just jumper the connector to ground the main fan should come on immediately. If it does then the switch is your problem. If it doesn't start tracing that wire back to the ECM.
Don't be surprised if the car gets pretty hot before the fan is turned on. I think mine switches around 215.
As far as the smaller fan mounted in front of the radiator you should be able to force it on by having the car running with the A/C set to max.
You said you replaced all the coolant sensors and switches but a quick test of the switch located on the passenger side head between cylinders 6 and 8 will determine if the switch is your problem. Just jumper the connector to ground the main fan should come on immediately. If it does then the switch is your problem. If it doesn't start tracing that wire back to the ECM.
Don't be surprised if the car gets pretty hot before the fan is turned on. I think mine switches around 215.
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
First check the 3 amp C. Fan fuse with an ohmeter! The ECM turns on the main fan at 228 F and the switch in the block between cylinders 1 and 3 turns on the auxilliary fan at 238 F by grounding one coil wire of the fan relay. The relay for the auxilliary fan is mounted behind the LH parking light If you ground the green/white wire on either fan relay, this will close the relay and the fan motor should run (ign sw has to be in run position). Also, to test the fan motor itself, jump 12v to the large black/red wire on the fan relay or unplug the motor and jump 12v to the motor plug. Also check for corrosion under the ground terminal for both motors and clean it to bright if cruddy.
Last edited by jfb; Jan 15, 2006 at 02:48 PM.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Originally Posted by Billdavis83
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I was going through the diagnostic section in my Haynes book and it said to jump terminals A and D on the relay harness. The problem is, my harness does not have a terminal D. Nor does my relay. If I jump terminals A and E, the fan runs. Any ideas what to do next?
I was going through the diagnostic section in my Haynes book and it said to jump terminals A and D on the relay harness. The problem is, my harness does not have a terminal D. Nor does my relay. If I jump terminals A and E, the fan runs. Any ideas what to do next?
What you need to do next is see if you are getting battery voltage to terminal C(Dark Blue) of the relay connector with the key in Run and check the C. Fan fuse. Also check for continuity between the relay's B and C terminals with an ohm meter.
If you are getting battery voltage at C or there is no continuity between the B and C terminals of the relay, your relay is bad.
Last edited by 86PACER; Jan 15, 2006 at 02:40 AM.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Interesting. He say's his 85 does not have a D terminal, but has an E instead like my 86. Your 85 wiring diagram shows it should be D in 85. Wire colors match though.
Last edited by 86PACER; Jan 15, 2006 at 03:23 AM.
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Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by Billdavis83
I am having troubles with the cooling fans on my 85. I have both a pusher and a puller fan. Neither will turn on when the car gets hot.
Originally Posted by Billdavis83
I was going through the diagnostic section in my Haynes book and it said to jump terminals A and D on the relay harness. The problem is, my harness does not have a terminal D. Nor does my relay. If I jump terminals A and E, the fan runs. Any ideas what to do next?
Also, my book mentioned if there is an auxilliary pusher fan, there is another relay mounted on the shroud. My car does not have this relay.
Also, my book mentioned if there is an auxilliary pusher fan, there is another relay mounted on the shroud. My car does not have this relay.
Originally Posted by cutchy
You said you replaced all the coolant sensors and switches but a quick test of the switch located on the passenger side head between cylinders 6 and 8 will determine if the switch is your problem. Just jumper the connector to ground the main fan should come on immediately.
RACE ON!!!
Last edited by CFI-EFI; Jan 15, 2006 at 01:23 PM.
Thread Starter
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Joined: Oct 2004
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Originally Posted by 86PACER
What you need to do next is see if you are getting battery voltage to terminal C(Dark Blue) of the relay connector with the key in Run and check the C. Fan fuse. Also check for continuity between the relay's B and C terminals with an ohm meter.
If you are getting battery voltage at C or there is no continuity between the B and C terminals of the relay, your relay is bad.
If you are getting battery voltage at C or there is no continuity between the B and C terminals of the relay, your relay is bad.
