Blower motor stays on high, even with key out

Question edited for clarity.
Question moved to model category.

Seems to be a known issue.

Blower Wont Shut Off - 1999-2013 Silverado & Sierra 1500

GM-Trucks.com https://www.gm-trucks.com > forums > topic > 11348...
May 9, 2010 - If the blower resistor is shorting prematurely then you most likely need a blower motor due to excess current draw.

Chevrolet Silverado 2007-2013: Why Won't My Blower Work?

ChevroletForum https://www.chevroletforum.com > how-tos > chevrole...
Another common problem will be the blower motor will stick in the ON position and never shut off.

Blower Motor Won't shut off ' GMC Truck Forum

gmfullsize.com https://www.gmfullsize.com > ... > Maintenance
Jan 17, 2011 - While driving today blower motor Kicked out, I turned up the fan speed and it kicked back in. Got to my destination, turned off the key and the ...

Missing: Classic. ‎' Show results with: Classic.

Heater/blower Won't Shut Off - Ask the GM Technician

GM-Trucks.com https://www.gm-trucks.com > forums > topic > 72853-...
Jan 11, 2008 - Cause is a mis-positioned harness from the blower motor assembly to the right I/P fuse block C4 causing harness rub through at right I/P metal ...

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

? 1:32
https://www.youtube.com/watch?v=PkltkvLDhIg
Apr 7, 2014 - Uploaded by MAY03LT
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 ...

www.dieselplace.com/.../76.../208669-blower-motor-wont-shut-off.html

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 ...

www.gmfullsize.com > General > Maintenance

Have you checked to see if the blower relay is stuck on ?

Your BCM (body control module), must have gone bonkers. Have it checked out. Might just need a little tweaking-like re-setting.
Good luck.

there could be partial contact in the blower controls which has resulted in total loss of contact, in blower speed affected. replacement of the entire blower control switch should resolve it

You have a bad blower motor relay, when the relay goes bad. It can freeze in the on position keeping the contact closed to run your blower motor. Inspect the blower motor relay and wire harness for any short due to burnt wire, this is a common issue with that year of Silverado's
Thank you for using fixya and good luck.

Run 12V directly to the motor and see if it will run, if it dosent than the motor is bad, if it does than the resister is bad, the resister makes the blower run and also regulates the speeds for the blower, but chanses are if it was making a high pitch squeel before it quit the motor went out.

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,

replace the blower motor speed control resistor

You will need a Blower motor resistor and maybe a blower motor resistor connector end. If you look under the dash on the passenger side(may need to remove smooth black cover, vents will be sticking out) you will see a connector going straight up into the blower motor resistor(7 wires/slightly in front of blower motor). Pull out the connector and check for melted terminals/wires. If no melted terminals just replace blower motor resistor with part # 89019088 per GM to revert to part before 04 in order to stop blower motor resistor relay from hanging. Let me know if i can help more.