Check engine light & cooling fan ?
Thread Starter
Drifting
Joined: Nov 2005
Posts: 1,361
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From: Downriver Mi.
Check engine light & cooling fan ?
Hi All,My check engine light is on,I checked for codes it only flashes code 12,Also the Cooling fan is on at start when cold &hot (runs constant)I hate to just throw parts at it,from the search I did it may be a fan relay,but the check engine with no code has me a little stumped,Has anyone had the same problem?85 model 
Race Director
Joined: Sep 2000
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From: The Top of Utah
The fan may be on as a part of the limp home mode. Have you waited for the fourth "12" to flash? Each code flashes 3 times before it moves on to the next code. One possible cause of both the light and the constant fan is a failed ECT sensor. You can do an ohm check to test it. Does your car have the auxiliary fan?
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RACE ON!!!
Thread Starter
Drifting
Joined: Nov 2005
Posts: 1,361
Likes: 0
From: Downriver Mi.
The fan may be on as a part of the limp home mode. Have you waited for the fourth "12" to flash? Each code flashes 3 times before it moves on to the next code. One possible cause of both the light and the constant fan is a failed ECT sensor. You can do an ohm check to test it. Does your car have the auxiliary fan?
RACE ON!!!
RACE ON!!!
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
I wasn't so concerned with whether the aux fan was running or not. I asked if you had an aux fan, because the main fan is wired differently depending on whether you have an aux fan or not, on an '85 only.
I ***-U-ME you mean that the check engine light came back on after the engine was restarted. It is supposed to come on when the ignition is turned to "on" before the engine is started. The recurring code is to be expected after the code is cleared, if the fault that caused to code hasn't been fixed.
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I ***-U-ME you mean that the check engine light came back on after the engine was restarted. It is supposed to come on when the ignition is turned to "on" before the engine is started. The recurring code is to be expected after the code is cleared, if the fault that caused to code hasn't been fixed.
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Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by MR NICE
All is well got a code 15 tracked it down to a broken wire 410ckt.FSM works great!
Originally Posted by CFI-EFI (post #2)
One possible cause of both the light and the constant fan is a failed ECT sensor.
RACE ON!!!
