I have a 1970 early Bronco and my issue is the heater fan is always running and it runs on high. I can't turn it off and I can't turn it to low speed. If the ignition is on, the blower fan is on at high speed. Is this an issue with the switch or the resistor?
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Ford 6R80 6 spd
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Heater Fan Always on High and Can't Turn Off
- Thread starter gpd43148
- Start date
SteveL
Huge chevy guy
If its bugging you pull the fuse until you have time to investigate.
Sounds like a bad switch or improper/bad wiring
- Joined
- Nov 3, 2003
- Messages
- 49,451
Can't be the resistor because it should not have power when the switch is in the OFF position.
So I say switch too.
Or the heater is wired incorrectly in the first place. For that you're going to have to put on your contortionist uniform and dive under the dash and look.
Luckily it's actually fairly accessible, and I think you can get to it from either side. Passenger side might be easier?
Good luck.
Paul
So I say switch too.
Or the heater is wired incorrectly in the first place. For that you're going to have to put on your contortionist uniform and dive under the dash and look.
Luckily it's actually fairly accessible, and I think you can get to it from either side. Passenger side might be easier?
Good luck.
Paul
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- Nov 3, 2003
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Oh, and welcome to classic too gpd! I know you've been here a few months now, but since this is your first post it's the first chance we've had to welcome you too.
Hope it's a simple prospect. First time I remember ever hearing of this particular problem.
Paul
Hope it's a simple prospect. First time I remember ever hearing of this particular problem.
Paul
Thank you all for the suggestions. I too thought it must be the switch. I just wanted to make sure it couldn't be the resistor before I removed the whole assembly to reach it. I will check and make sure all of the wires are connected to the switch properly. If they are connected, I guess I will buy a switch and replace. Thanks Again!!
- Joined
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You can still test the switch before buying a new one if you have a volt/ohm-meter.
The wiring would have to be cobbled together or butchered for it to be the wiring I would think, since the switch is just standard blade connectors and the short harness to the heater is pretty straightforward.
But either way, it's easy to at least see what's going on with the wiring. Maybe the PO had a failed switch and needed heat so they ran a wire directly from the backside of the ignition switch to the heater motor.
Lots of odd things are discovered under the dashes of previously owned Broncos!
Good luck.
Paul
The wiring would have to be cobbled together or butchered for it to be the wiring I would think, since the switch is just standard blade connectors and the short harness to the heater is pretty straightforward.
But either way, it's easy to at least see what's going on with the wiring. Maybe the PO had a failed switch and needed heat so they ran a wire directly from the backside of the ignition switch to the heater motor.
Lots of odd things are discovered under the dashes of previously owned Broncos!
Good luck.
Paul
Well, I crawled under the dash this weekend to inspect the wiring and discovered the orange wire that connects the blower motor to the resistor is cut. I then discovered a toggle switch under the dash that is wired to the blower motor and that is how the PO regulated the blower. I have no low speed but at least I can turn it on and off for now.
