AIR CONDITIONING SYSTEM Blower Motor Circuit

DESCRIPTION

The blower motor with fan sub-assembly is operated by signals from the air conditioning amplifier assembly. Blower motor speed signals are transmitted in accordance with changes in the duty ratio.

WIRING DIAGRAM

A01MIAXE01
*a from Auxiliary Battery
*b Air Conditioning Amplifier Assembly
*c Blower Motor with Fan Sub-assembly

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Air Conditioner / Active Test.

    5. Check the operation by referring to the table below.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Blower Motor Blower motor with fan sub-assembly Min.: 0, Max.: 31 -

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Blower Motor
      Result
      Result Proceed to
      OK A
      NG (Blower motor with fan sub-assembly does not operate) B
      NG (Blower motor with fan sub-assembly operates but does not change speed) C

    A

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

    C

    GO TO STEP 4 Click here

    B

  2. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - POWER SOURCE CIRCUIT)


    1. A01MJD8C07
      *a

      Front view of wire harness connector

      (to Blower Motor with Fan Sub-assembly)

      Disconnect the blower motor with fan sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G36-3 (GND) - Body ground Always Below 1 Ω

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      G36-1 (+B) - Body ground Power switch off 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the G36 blower motor with fan sub-assembly connector.

    2. Disconnect the G43 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G36-2 (SI) - G43-22 (BLW) Always Below 1 Ω
      G36-2 (SI) or G43-22 (BLW) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Reconnect the G36 blower motor with fan sub-assembly connector.

    2. Reconnect the G43 air conditioning amplifier assembly connector.

    3. Turn the power switch on (IG).

    4. Turn the blower switch on (LO).

    5. A01MIQAC04
      *a

      Component with harness connected

      (Air Conditioning Amplifier Assembly)

      Measure the waveform between terminal G43-22 (BLW) of the air conditioning amplifier assembly and body ground.

      OK
      Waveform is similar to that shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

      Item Content
      Tool setting 1 V/DIV., 500 μs/DIV.
      Vehicle condition

      • Power switch on (IG)

      • Blower switch: LO
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here