Blower fan only works on high

03 - 06 Silverado/Sierra blower stays on with key off (how to ...

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The HVAC blower in this 2003 Silverado stays on speed 5 even with the key off. Here's how to turn speed 5 of the blower off(while keeping speeds 1-4) and ho. ... How to replace blowermotor resistor in Chevrolet Silverado - Duration: 5:06. ... 2004Tahoe rear brake service (replace pads, clean/lube slides, ...

Blower motor won't shut off. - Diesel Place : Chevrolet and GMC ...

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Jan 10, 2008 - 11 posts - ‎7 authors
I have read through many posts on blower motor issues but no one had the same issue I have. ... If I shut the truck off, it still won't shut off and runs until the battery is dead.... 2002 GMC Sierra RCLB 1500 4X4 SLE, 7 1/2' Fisher plow.

Question - Blower Motor Won't shut off ' Chevy Truck Forum ' GMC ...

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I'm going to assume you have the manual control version. The relay in the resistor allows the fan to run on high and bypass the resistor circuits. There is a 40amp blower fuse for high speed and a 30amp fuse for the other speeds. The motor is grounded thru the resistor.
Do you have power and ground at the motor on any of the settings ? ?

if you got heat on all speeds and the blower motor is working properly then you probably need a new HVAC switch.

Likely the blower motor resistor. located right next to the blower motor, this device is resposible for reducing the voltage suplied to the motor. when it fails you may loose some or all speeds of the motor

I’m happy to assist further over the phone at https://www.6ya.com/expert/samuel_dda9c48bb7ffbfd3

switch has failed and needs replaced would be my suggestion....good luck...

you probably need new control switch.

problem in your blower switch

Most likely the blower motor resistor. It's mounted next to the blower motor under the dash. Also check the 7 wire plug going to it, GM had a problem with that plug, and the wiring getting hot and melting. The plug is $68.00 from the dealership. One of my customer's car had the same problem.

I had a truck about the same year with the same problem, it was the wiring harness, but id check the resistor and the fan first before replacing anythings,

The blower motorresister is bad. It controls the blower speeds for low, medium speeds. It is in the air stream of the blower plenum, usually under the hood on the passenger side at the fire wall.

Usually held in with 2 screws and has a wire connector with 4 or 5 wires in it. You can do this repair. Part is available at most auto stores.