FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Test O: The Blower Motor Is Inoperative - DATC/EATC

PINPOINT TEST O: THE BLOWER MOTOR IS INOPERATIVE - DATC/EATC

Normal Operation
Under normal operation, the blower motor relay coil receives a ground from the HVAC module - electronic automatic temperature control (EATC) or HVAC module - dual automatic temperature control (DATC) module through circuit CH123 (VT/GN). The coil receives ignition voltage through circuit 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 HVAC module - DATC or HVAC module - 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.

This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Blower motor relay
- Blower motor control
- HVAC module - EATC
- HVAC module - DATC
- Blower motor


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