Test I: The Blower Motor Does Not Operate Correctly

PINPOINT TEST I: THE BLOWER MOTOR DOES NOT OPERATE CORRECTLY

Normal Operation
Under normal operation, the blower motor is provided ground from the blower resistor through circuit VH301 (YE/BU). The resistor gets a ground from circuit GD138 (BK/WH) in the lowest blower setting. In MED-LO and MED-HI the resistor gets ground from the blower motor switch through circuit CH428 (GN/WH) or CH429 (GY/BN), depending on selected speed. In HI, the blower motor is grounded directly through the blower motor switch from circuit VH301 (YE/BU) to circuit GD138 (BK/WH). The blower switch receives its ground from circuit GD138 (BK/WH).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Blower motor resistor
- Blower motor switch

I1-I3:

I3-I4:

I5-I8:

I8-I9: