The HVAC blower motor will not turn off?

2006 CHEVROLET SILVERADO
142,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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TRISTIN ANDEWAY
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AC/heater blower fan won’t shut off after shutting off truck and keys out of the ignition. Started with having little to no heat and no control of fan speed. Every other setting seems to work. Just recently I replaced the blower motor resistor and connectors, now the fan runs on high all the time and still don’t have fan speed control. Checked all the fuses and tried resetting the HVAC control module with no luck. Any advice is greatly appreciated!
Jan 10, 2023 at 8:28 PM
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STRAILER
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It sounds like you have a defective speed control resistor (module) because this is what happens when the resistor goes out. Also, I would check the ground circuit which this guide can help with.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Here are the blower motor wiring diagrams so you can see how the system works, the ground is located at the right pillar A. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem.

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Jan 11, 2023 at 10:59 AM
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TRISTIN ANDEWAY
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I took out the module I replaced and switched it out for another one from O'Reilly's but still had the same problem. I had some trouble locating the ground circuit, even though I didn’t take too much time to look for it. Could it be the blower itself or possibly the climate control panel?
Jan 18, 2023 at 7:40 PM
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STRAILER
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I don't think the blower motor will cause that, but the HVAC controller might, here is how you can change it out in the diagrams below.
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Jan 20, 2023 at 9:18 AM