After being parked the HVAC blower motor does not work

Tiny
JACOBANDNICKOLAS
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Okay, you confirmed there is power to the blower motor blue/white wire. You confirmed there is ground, and you had 4.57v from the pulse width modulator. The fan should be running.

Do me a favor. Check to see if the voltage drops when you request the fan motor on. We must have a weak connection at some point.

Let me know.

Joe
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Thursday, July 21st, 2022 AT 6:10 PM
Tiny
MALLYBOY
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No there is no voltage drop when I on blower motor on.
What I need now is to know why the Service Engine Light has stopped illuminating after testing another fuse box on the vehicle?
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Friday, July 22nd, 2022 AT 12:48 AM
Tiny
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If you replaced the box, you had power off to everything. I suspect you reset things. If there is no voltage drop, it sounds like the problem could be at the switch. I'm not sure what to tell you. You have power where it needs to be, the motor is good, you have ground, it should run. We have to be missing something simple. When you checked for a voltage drop, did you do it at the motor?

Joe
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Saturday, July 23rd, 2022 AT 8:13 PM
Tiny
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Thank you once again, I have come to tell you that I replaced another used blower motor but there's something strange on tje PWM wire from A/C amplifier. When you increase the speed of blower, instead of the voltage to drop as speed is increasing, the voltage will also be increasing. When I on the blower motor, it didn't operate and I remove the PWM-wire and ground it to negative wire and the blower run at its maximum speed. I connect it back but still it didn't operate. At this point I suspect faulty AC amplifier.
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Thursday, August 4th, 2022 AT 2:02 PM
Tiny
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Hi,

I agree with your diagnosis. Also, when you increase fan speed, you are increasing voltage, so what you said sounds correct.

Let me know if the amplifier takes care of the issue.

Take care,

Joe
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Thursday, August 4th, 2022 AT 5:00 PM
Tiny
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Let me know if the amplifier takes care of the issue. Yes.
I replaced another A/C amplifier and the problem solved.
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Thursday, August 25th, 2022 AT 7:03 PM
Tiny
JACOBANDNICKOLAS
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Hi,

Thank you for the update. I had a feeling that is where the issue was coming from and I'm glad it's fixed.

Take care of yourself and feel free to come back anytime in the future.

Joe
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Thursday, August 25th, 2022 AT 8:06 PM

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