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These vehicles had fairly common issues with this due to the blower control module. What you can do is remove the plug at the blower motor under the passenger side of the dash and use a voltmeter with one probed in each cavity of the connector to check for voltage. If it changes at each speed and goes to 12 volts the motor is bad, if not it's most likely the module. Also inspect the connectors for burning at the contacts which is another common issue with these. I'll post the wiring diagrams below.
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Wednesday, January 8th, 2020 AT 11:32 AM