Test P: The Blower Motor Does Not Operate Correctly - DATC/EATC

PINPOINT TEST P: THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY - DATC/EATC

P1-P3:

P3-P5:

P5-P7:

Normal Operation
Under normal operation, the blower motor relay coil receives a ground from the electronic automatic temperature control (EATC) or dual automatic temperature control (DATC) module through circuit CH123 (VT/GN). The coil receives ignition voltage through circuit A_CBP23 (BN/YE). Voltage is supplied to the relay switch contact through circuit SBB04 (GN/RD). When the relay coil is energized, voltage is delivered to the blower motor control module through circuit CH402 (YE/GN). Ground for the blower control module is provided by circuit GD115 (BK/GY). The DATC/EATC module provides a pulsed ground to the blower control module through circuit VH101 (WH/VT) to control the blower speed. Voltage for the motor is provided through circuit CH218 (GN/VT) from the blower control module. Ground for the motor is provided through circuit VH301 (YE/BU) from the blower control module.

Possible Causes
- A short to ground in circuit VH101 (WH/VT), VH301 (YE/BU) or CH123 (VT/GN)
- A short to voltage in circuit CH218 (GN/VT)
- Blower motor control module
- Blower motor relay
- DATC/EATC module