See if the red wire at the speed controller has power. This guide can help test the wire with the key on HVAC system on. Also, check the ground as well. here is guide that will help you with the test. I also gave you the HVAC and blower motor wiring diagrams so you can see how the system works.
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
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Friday, November 11th, 2022 AT 9:21 AM