A/C switch
FTE Legend
Joined: Nov 2015
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From: Angier, NC
Does it only works when the switch is on high or the blower blows high (fast) on all switch settings?
If works on high only then I would say it is the blower motor resister that is bad.
I want to say it is on the motor bay side of the heater box by the blower motor area.
Dave ----
If works on high only then I would say it is the blower motor resister that is bad.
I want to say it is on the motor bay side of the heater box by the blower motor area.
Dave ----
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From: Virginia
Most likely the blower resistor. It's always mounted in the ductwork, so the air from the fan can cool it. I have had several here lately go bad, and the resistors have been good, it's a thermal fuse they add in there that goes bad. It looks like a little silver cylinder thing in there, and is exactly like the ones they use in coffee makers.
The old cars didn't have this fuse, and I have bypassed it before and it worked fine. But I will leave that up to you. They put it in there for some sort of safety reason I suppose, so you may be taking some risk by bypassing the thermal fuse.
The old cars didn't have this fuse, and I have bypassed it before and it worked fine. But I will leave that up to you. They put it in there for some sort of safety reason I suppose, so you may be taking some risk by bypassing the thermal fuse.
Lead Driver
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Lots of good info about the blower motor resistor pack in this thread:
https://www.ford-trucks.com/forums/1...the-cab-2.html
https://www.ford-trucks.com/forums/1...the-cab-2.html
FTE Legend
Joined: Nov 2015
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From: Angier, NC
Fords may be different than my 02 Dodge where it would only work on high but the resister would be the first place I would look.
Good luck and let us know how you make out, could help others.
Dave ----
Good luck and let us know how you make out, could help others.
Dave ----
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From: Virginia
This description sounds different. It blows on high speed in all the different speed settings?
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Lead Driver
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Ah, there seems to have been a misunderstanding. I thought you meant the fan only worked with the switch in the HI position. Your latest description sounds like a bad switch.
Does your truck have factory AC? It will have four rectangular registers set into the dash.
A/C & Heater - ???Gary's Garagemahal
Or no AC at all?
Heater - ???Gary's Garagemahal
Or does it have aftermarket or dealer-installed AC? This will be an underdash unit, possibly with its own switch. No idea on that wiring, although the factory heater fan should be as at the previous link.
Does your truck have factory AC? It will have four rectangular registers set into the dash.
A/C & Heater - ???Gary's Garagemahal
Or no AC at all?
Heater - ???Gary's Garagemahal
Or does it have aftermarket or dealer-installed AC? This will be an underdash unit, possibly with its own switch. No idea on that wiring, although the factory heater fan should be as at the previous link.
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Inquiring minds want to know...
FTE Legend
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From: Angier, NC
Dave ----
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