Thank you for the reply Terry. I have the manual CC and there are no diagnostics built in as ther is no LCD panel. This noise is present with the blower out of the dash. AC and heat work fine just the squeal when the blower is powered through the regulator. I could hold the assembly in my hand and press on the contact or lift the contact and the noise will go away. I took the regulator off of the blower and same result the noise is deffinately coming from the regulator. I just thought it was all solid state and should not buzz internally. The noise is about 6Khz but varies with the speed. My thought was could an overcurrent condition cause the regulator to buzz. If I power the blower from a seperate DC supply from 3 volts to 12 volts the motor is quiet and the current looks ok.

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Dave
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