Where is the blower resistor located?

TSILVA4

MEMBER
1999 CADILLAC DEVILLE
4.7L
V8
2WD
94,000 MILES

Where is the resistor for the A/C blower motor located on my car listed above?

Tuesday, August 19th, 2025 AT 8:48 AM

7 Replies

STEVE W.

MECHANIC
15,231 POSTS

There isn't one for the front blower motor. It uses a solid state pulse width modulation controller to regulate the blower speed. That module is built into the blower motor itself. What seems to be the problem with it?

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Tuesday, August 19th, 2025 AT 4:47 PM

TSILVA4

MEMBER
5 POSTS

The blower comes on low even when the ignition is off and it drains the battery. Then when I run the car, the fan only runs on low.

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Wednesday, August 20th, 2025 AT 8:20 AM

STEVE W.

MECHANIC
15,231 POSTS

OK, to test if it's the blower control you would need to disconnect the connection at connector 2 on the programmer, it is located behind the glove box. That would isolate the blower module. If it still stays on then you know it's the blower motor.

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Wednesday, August 20th, 2025 AT 10:55 AM

TSILVA4

MEMBER
5 POSTS

Do you happen to have a picture of the programmer?

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Wednesday, August 20th, 2025 AT 11:54 AM

TSILVA4

MEMBER
5 POSTS

I found it and discounted both connectors and the fan kept running

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Wednesday, August 20th, 2025 AT 2:13 PM

TSILVA4

MEMBER
5 POSTS

*disconnected

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Wednesday, August 20th, 2025 AT 2:14 PM

STEVE W.

MECHANIC
15,231 POSTS

OK, you have a bad blower motor controller. That is part of the blower motor itself. It is under the hood on the firewall. You remove the brace above it, move the harness out of the way and remove the 3 or 5 screws that secure the blower in place. The new one will have 3 holes only. Reverse the process to install the new one.

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