AIR CONDITIONING SYSTEM Blower Motor Circuit

DESCRIPTION

The blower with fan motor sub-assembly (blower motor) 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

A003YOJE03

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the intelligent tester on.

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

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

      Air Conditioner
      Tester Display Test Part Control Range Diagnostic Note
      Blower Motor Blower with fan motor sub-assembly (blower motor) Min.: 0, Max.: 31 -
      OK
      Blower with fan motor sub-assembly (blower motor) operates and blower motor speed level changes.
      Result
      Result Proceed to
      OK A
      NG (Blower motor does not operate) B
      NG (Blower motor operates but does not change speed) C

    B

    CHECK HARNESS AND CONNECTOR (BLOWER WITH FAN MOTOR (BLOWER MOTOR) - BODY GROUND) Click here

    C

    INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

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

  2. CHECK HARNESS AND CONNECTOR (BLOWER WITH FAN MOTOR (BLOWER MOTOR) - BODY GROUND)


    1. Disconnect the H13 blower with fan motor sub-assembly (blower motor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H13-3 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (BLOWER WITH FAN MOTOR (BLOWER MOTOR) - POWER SOURCE)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      H13-1 (+B) - Body ground Power switch off 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR - AIR CONDITIONING AMPLIFIER)


    1. Disconnect the H85 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H85-23 (BLW) - H13-2 (SI) Always Below 1 Ω
      H85-23 (BLW) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT BLOWER WITH FAN MOTOR SUB-ASSEMBLY (BLOWER MOTOR)


    1. Reconnect the H13 blower with fan motor sub-assembly (blower motor) connector.

    2. A003Y06E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      H85-23 (BLW) - Body ground Power switch off 4.5 to 5.5 V

    NG

    REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY Click here

    OK

  6. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. A003YF2E33
      Text in Illustration
      *a

      Component with harness connected

      (Air Conditioning Amplifier Assembly)

      Remove the air conditioning amplifier assembly.

    2. Reconnect the H85 air conditioning amplifier assembly connector.

    3. Turn the power switch on (IG).

    4. Set the blower speed to low.

    5. Measure the waveform between terminal H85-23 (BLW) of the air conditioning amplifier assembly and body ground.

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

      Power switch on (IG)

      Blower set to low
      OK
      Waveform is as shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.


    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

    REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY Click here