FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Test O: The Blower Motor Does Not Operate Correctly - EATC

PINPOINT TEST O: THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY - EATC

Normal Operation
The blower motor control module receives a 1-2 volt signal from the electronic automatic temperature control (EATC) module through circuit 260 (RD/OG) to determine the desired blower motor speed. The EATC module receives a feedback voltage from the blower motor control module through circuit 752 (YE/RD) to determine actual blower motor speed. When the highest blower motor setting is selected, the EATC module sends 12 volts to the blower control module through circuit 754 (LG/WH). Ground for the motor is provided through circuit 515 (OG/RD) from the blower control module.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Blower motor control module
- EATC module


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