Test J: The Auxiliary Blower Motor Does Not Operate Correctly
PINPOINT TEST J: THE AUXILIARY BLOWER MOTOR DOES NOT OPERATE CORRECTLYNormal Operation
Under normal operation, the auxiliary blower motor relay 1 coil receives a ground through circuit 57 (BK). The relay 1 coil receives voltage from circuit 752 (YE/RD) if any position but OFF is selected. Voltage is supplied to the relay 1 switch from circuit 884 (YE/BK). When the relay 1 coil is energized, voltage is delivered to the blower motor through circuit 371 (PK/WH). Ground for the motor is provided through circuit 261 (OG/BK) from auxiliary blower motor relay 2. In any speed except HI, ground is provided to relay 2 switch through the auxiliary resistor. Ground for the auxiliary resistor is provided by circuit 57 (BK). In HI, ground is provided to relay 2 switch through 57 (BK).
The auxiliary blower motor relay 2 coil receives voltage from circuit 752 (YE/RD) if any position but OFF is selected. When the auxiliary blower motor switch is in the HI position, ground is provided to the relay 2 coil through circuit 757 (RD/WH). When relay 2 is energized, the auxiliary blower motor is grounded directly through circuit 57 (BK).
Under normal operation, the auxiliary blower motor is provided a ground from the resistor through circuit 515 (OG/RD). The resistor gets a ground from the rear auxiliary blower switch, depending on selected speed, through circuit 752 (YE/RD) or circuit 751 (DB/WH). The rear auxiliary blower switch is provided ground through circuit 57 (BK).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Auxiliary blower motor switch
- Auxiliary blower motor resistor
- Auxiliary blower motor relay 1
- Auxiliary blower motor relay 2
J1-J2:
J2-J5:
J5-J7:
J8-J10:
J11-J13:
