Cabin Blower Fan Speed Dropping Resistor
wiswind
08-13-2006, 06:27 PM
Problem, no cabin fan for heat / air conditioning, or only has 1 speed.
Solution, defective fan speed dropping resistor.
My fan died, only worked on the fastest speed, or not at all.
I ordered a new resistor for about $21, including shipping and tax (I live in Wisconsin, same state as Rock Auto) from www.rockauto.com
The cabin fan dropping resistor is located under the glove box.
It is held in place by 2 x 8mm bolts, and has an electrical connector.
My electrical connector took some work to get free as it was somewhat stuck in place.
Cause of failure in my case seems to have been moisture, causing the metal mounting clips for the resistors to rust, and break.
If the new one lasts 10 years like the original, I will be in good shape.
The dropping resistor assembly is several coils of wire, which are the dropping resistors for the various fan speeds.
There is also a small solid resistor that serves as a thermal protection device.
If the fan should become physically blocked, short out, or otherwise fail such that it caused a big current draw, the small thermal resistor would burn open, preventing the fan motor from catching on fire.
I took 2 pictures of the dropping resistor assembly, one as you will see it when you look up under the dash, under the glove compartment.
The other picture is with the 2 bolts removed, and I have it partly out of the opening.
The link in my signature will take you to the pictures.
Solution, defective fan speed dropping resistor.
My fan died, only worked on the fastest speed, or not at all.
I ordered a new resistor for about $21, including shipping and tax (I live in Wisconsin, same state as Rock Auto) from www.rockauto.com
The cabin fan dropping resistor is located under the glove box.
It is held in place by 2 x 8mm bolts, and has an electrical connector.
My electrical connector took some work to get free as it was somewhat stuck in place.
Cause of failure in my case seems to have been moisture, causing the metal mounting clips for the resistors to rust, and break.
If the new one lasts 10 years like the original, I will be in good shape.
The dropping resistor assembly is several coils of wire, which are the dropping resistors for the various fan speeds.
There is also a small solid resistor that serves as a thermal protection device.
If the fan should become physically blocked, short out, or otherwise fail such that it caused a big current draw, the small thermal resistor would burn open, preventing the fan motor from catching on fire.
I took 2 pictures of the dropping resistor assembly, one as you will see it when you look up under the dash, under the glove compartment.
The other picture is with the 2 bolts removed, and I have it partly out of the opening.
The link in my signature will take you to the pictures.
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