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

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

M1-M3:

M3-M5:

M5-M7:

M8-M9:

Normal Operation
Under normal operation, the blower motor is provided a ground from the blower resistor through circuit CH430 (VT/OG)/(BK/RD). The resistor gets a ground from circuit GD116 (BK/VT) 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)/(RD) or CH429 (GY/BN)/(BN), depending on selected speed. In HI, the blower motor is grounded directly through the blower motor switch from circuit CH430 (VT/OG)/(BK/RD) to circuit GD116 (BK/VT). The blower switch receives its ground from circuit GD116 (BK/VT)/(GN).

Possible Causes
- An open in circuit GD116 (BK/VT)/(GN), CH428 (GN/WH)/(RD), CH429 (GY/BN)/(BN) or CH430 (VT/OG)/(BK/RD)
- A short to ground in circuit CH428 (GN/WH)/(RD), CH429 (GY/BN)/(BN) or CH430 (VT/OG)/(BK/RD)
- A short together in circuits CH428 (GN/WH)/(RD), CH429 (GY/BN)/(BN) or CH430 (VT/OG)/(BK/RD)
- Blower motor resistor
- Blower motor switch