Test O: The Blower Motor Does Not Operate Correctly - EMTC

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

O1-O3:

O3-O4:

O5-O8:

O8-O9:

Normal Operation
Under normal operation, the blower motor is provided a ground from the blower resistor through circuit CH430 (VT/OG). The resistor gets a ground from circuit GD138 (BK/WH) in the lowest blower setting. In MED-LO and MED-HI the resistor gets a 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 CH430 (VT/OG) to circuit GD138 (BK/WH). The blower switch receives its ground from circuit GD138 (BK/WH).

Possible Causes
- An open in circuit GD138 (BK/WH), CH428 (GN/WH), CH429 (GY/BN) or CH430 (VT/OG)
- A short to ground in circuit CH428 (GN/WH), CH429 (GY/BN) or CH430 (VT/OG)
- A short together in circuits CH428 (GN/WH), CH429 (GY/BN) or CH430 (VT/OG)
- Blower motor resistor
- Blower motor switch