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Test Q: The Blower Motor Does Not Operate Correctly - DATC

PINPOINT TEST Q: THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY - DATC


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Normal Operation
Under normal operation, the blower motor control module receives a 1-2 volt signal from the DATC module through circuit 776 (OG/BK) to determine the desired blower motor speed. The DATC module receives a feedback voltage from the blower motor control module through circuit 937 (RD/WH) to determine actual blower motor speed. When the highest blower motor setting is selected, the DATC module sends 12 volts to the blower control module through circuit 755 (BN/WH).

Possible Causes
- An open, short to voltage, ground or together in circuits 776 (OG/BK), 937 (RD/WH) or circuit 755 (BN/WH).
- Blower motor control module.
- DATC module.