86 heater fan problem
Thread Starter
5th Gear
Joined: Nov 2002
Posts: 5
Likes: 0
From: Otisco Ind
86 heater fan problem
The heater fan on my 86 will completly run the battery dead when its parked overnight. I have run the diagnostic test on the system and it shows no faults or errors. I can pull the plug on the blower fan and the battery stays charged. Anyone have any ideas????? It's cold and snowing here in So. Ind. So I need to fix this quick.
Thread Starter
5th Gear
Joined: Nov 2002
Posts: 5
Likes: 0
From: Otisco Ind
Re: 86 heater fan problem (Chucks87)
Sorry took so long to get back to you had some computer problems!!!!!!!!!!!
The fan does not run with the ignition off sometimes. The fan on a couple of occasions has run very slowly with the ignition off. The last time I checked it was about a week ago. I put a mark on the fan blower and it never moved. But still the next morning the battery was dead. (New Battery). So I unplugged the Fan wire and the car has set for about three days through some pretty cold Temps. and it started right up with no noticable battery problems...
The fan does not run with the ignition off sometimes. The fan on a couple of occasions has run very slowly with the ignition off. The last time I checked it was about a week ago. I put a mark on the fan blower and it never moved. But still the next morning the battery was dead. (New Battery). So I unplugged the Fan wire and the car has set for about three days through some pretty cold Temps. and it started right up with no noticable battery problems...
Safety Car
Joined: Aug 1999
Posts: 3,868
Likes: 1
From: Chino Hills CA
Cruise-In III & VI Veteran
Re: 86 heater fan problem (Doulong)
Hard to say but you may have a bad relay. The fan has to have the relay ON to make it run. Does the fan work correctly when the car is running?
Thread Starter
5th Gear
Joined: Nov 2002
Posts: 5
Likes: 0
From: Otisco Ind
Re: 86 heater fan problem (Chucks87)
The fan runs operates correctly. My thought is the blower motor control may have a short. Is that possible???? And is there anyway to check it. I have the shop manual from chevrolet. But it does not show any relay in that circuit. Only the control.
Melting Slicks
Joined: Feb 2002
Posts: 2,699
Likes: 2
From: The Black Hole LA
Re: 86 heater fan problem (Doulong)
I've got the same exact problem. I have replaced the blower motor module with no results. The fan stays on sometimes when the car is off, but it is not on full blast just slowly turning. My next course of action is to replace the electric climate controls on the inside of the car, cause I know there is a short there too, but don't know if it is causing the fan thing. Any other suggestions would be greatly appreaciated cause if that does not work I guess it is time to start tracing wires.
Thread Starter
5th Gear
Joined: Nov 2002
Posts: 5
Likes: 0
From: Otisco Ind
Re: 86 heater fan problem (hz900)
Let me know what you find. I may start with the fan itself. I think it could have some bad windings in the motor that are pulling the juice out of the battery
Melting Slicks
Joined: Feb 2002
Posts: 2,699
Likes: 2
From: The Black Hole LA
Re: 86 heater fan problem (Doulong)
I did not think that was possible. The fan is one from AutoZone. I know they are not known for their electrical parts reliability. Does anyone think that it could be the fan motor going bad and how do you test this.
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