[Jterr]

2002 F-150
AC Fan only works on High. Fuse or switch??

 

[Action]

Could be the switch and the most likely issue ....
If the inside blower fan only works on high the issue is usually the blower motor resistor.
The resistor steps down the electrical signal to achieve slower speeds. Except high. On high the blower motor gets all of he power.

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[Jterr]

Could be the switch and the most likely issue ....
If the inside blower fan only works on high the issue is usually the blower motor resistor.
The resistor steps down the electrical signal to achieve slower speeds. Except high. On high the blower motor gets all of he power.

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So is there a way I can check?

 

[Action]

Should look similar to the attached.

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[Action]

Yes! With ohm meter.
Disconnect the connector at the resistor
Check for continuity across the multiple circuits in the resistor.
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A copy of the circuit I found on the net.

 

[Jterr]

Should look similar to the attached.

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View attachment 51648

Where is this at the switch are the blower itself. Do I have to remove the dash??

 

[Action]

I do not know exactly, because I have never worked you that gen F Series.
In general, the resistor is located in or near the HVAC plenum chamber. Close to the blower fan.
It generates a lot of heat, so location of the resistors in the plenum is done to cool the resistors.
However, the unit is usually bolted to the side of the plenum.
Dash removal is almost never needed.
Removing the glove box is a common thing.

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[Jterr]

I do not know exactly, because I have never worked you that gen F Series.
In general, the resistor is located in or near the HVAC plenum chamber. Close to the blower fan.
It generates a lot of heat, so location of the resistors in the plenum is done to cool the resistors.
However, the unit is usually bolted to the side of the plenum.
Dash removal is almost never needed.
Removing the glove box is a common thing.

Action

Thanks