AIR CONDITIONING SYSTEM(for Manual Air Conditioning System) Blower Motor Circuit

DESCRIPTION

When the No. 2 heater control sub-assembly is operated, the heater relay will turn on to allow current to flow to the blower motor and then the motor will start rotating. Operating the No. 2 heater control sub-assembly switches the current flow between the blower resistor and body ground, thus, shifting the rotation speed of the blower motor with fan sub-assembly.

WIRING DIAGRAM

A01TDHPE01

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE


  1. INSPECT HEATER RELAY (HTR)


    1. A01T9RMC05
      *a

      Component without harness connected

      (Heater Relay (HTR))

      Remove the heater relay (HTR).

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage is applied between terminals 1 and 2 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEATER RELAY (HTR)

    OK

  2. INSPECT BLOWER MOTOR WITH FAN SUB-ASSEMBLY


    1. Disconnect the E64 blower motor with fan sub-assembly connector.

    2. A01TBI4C04
      *A for LHD
      *B for RHD
      *a

      Component without harness connected

      (Blower Motor with Fan Sub-assembly)

      Connect a positive (+) lead from the battery to terminal 2 and a negative (-) lead to terminal 1, and check that the motor operates.

      OK
      The blower motor with fan sub-assembly operates smoothly.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY Click here

    OK

  3. INSPECT BLOWER RESISTOR


    1. A01T9BMC10
      *A for LHD
      *B for RHD
      *a

      Component without harness connected

      (Blower Resistor)

      Remove the blower resistor.

      Click here

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      4 (E) - 1 (HI) Always 3.12 to 3.60 Ω
      2 (M1) - 1 (HI) Always 1.45 to 1.67 Ω
      3 (M2) - 1 (HI) Always 0.52 to 0.60 Ω
      Standard Resistance
      for RHD
      Tester Connection Condition Specified Condition
      1 (E) - 4 (HI) Always 3.12 to 3.60 Ω
      3 (M1) - 4 (HI) Always 1.45 to 1.67 Ω
      2 (M2) - 4 (HI) Always 0.52 to 0.60 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BLOWER RESISTOR Click here

    OK

  4. INSPECT NO. 2 HEATER CONTROL SUB-ASSEMBLY


    1. A01T8DVC01
      *a

      Component without harness connected

      (No. 2 Heater Control Sub-assembly)
      *1 Blower Switch OFF Position
      *2 Blower Switch LO Position
      *3 Blower Switch M1 Position
      *4 Blower Switch M2 Position
      *5 Blower Switch HI Position

      Remove the No. 2 heater control sub-assembly.

      Click here

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (LO), 6 (HI), 8 (M1), 10 (M2) - 5 (E) Blower switch: OFF 10 kΩ or higher
      1 (LO) - 5 (E) Blower switch: LO Below 1 Ω
      1 (LO), 8 (M1) - 5 (E) Blower switch: LO - M1 Below 1 Ω
      1 (LO), 8 (M1) - 5 (E) Blower switch: M1 Below 1 Ω
      1 (LO), 8 (M1), 10 (M2) - 5 (E) Blower switch: M1 - M2 Below 1 Ω
      1 (LO), 10 (M2) - 5 (E) Blower switch: M2 Below 1 Ω
      1 (LO), 10 (M2), 6 (HI) - 5 (E) Blower switch: M2 - HI Below 1 Ω
      1 (LO), 6 (HI) - 5 (E) Blower switch: HI Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO. 2 HEATER CONTROL SUB-ASSEMBLY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - HEATER RELAY (HTR))


    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Heater relay terminal 2 - E62-14 (HR) Always Below 1 Ω
      Heater relay terminal 2 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (NO. 2 HEATER CONTROL SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      E62-17 (SBLW) - E70-1 (LO) Always Below 1 Ω
      E62-17 (SBLW) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (BLOWER RESISTOR - NO. 2 HEATER CONTROL SUB-ASSEMBLY)


    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      E66-1 (HI) - E70-6 (HI) Always Below 1 Ω
      E66-3 (M2) - E70-10 (M2) Always Below 1 Ω
      E66-2 (M1) - E70-8 (M1) Always Below 1 Ω
      E66-4 (E) - Body ground Always Below 1 Ω
      E70-5 (E) - Body ground Always Below 1 Ω
      E66-1 (HI) - Body ground Always 10 kΩ or higher
      E66-3 (M2) - Body ground Always 10 kΩ or higher
      E66-2 (M1) - Body ground Always 10 kΩ or higher
      Standard Resistance
      for RHD
      Tester Connection Condition Specified Condition
      E66-4 (HI) - E70-6 (HI) Always Below 1 Ω
      E66-2 (M2) - E70-10 (M2) Always Below 1 Ω
      E66-3 (M1) - E70-8 (M1) Always Below 1 Ω
      E66-1 (E) - Body ground Always Below 1 Ω
      E70-5 (E) - Body ground Always Below 1 Ω
      E66-4 (HI) - Body ground Always 10 kΩ or higher
      E66-2 (M2) - Body ground Always 10 kΩ or higher
      E66-3 (M1) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - NO. 2 HEATER CONTROL SUB-ASSEMBLY)


    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      E64-1 - E70-6 (HI) Always Below 1 Ω
      E64-1 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - HEATER RELAY (HTR))


    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Heater relay terminal 3 - E64-2 Always Below 1 Ω
      Heater relay terminal 3 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR