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

B004QZPE08
*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. Perform the Active Test according to the display on the GTS.


      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 6 Click here

    B

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


    1. Disconnect the F10 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
      F10-1 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (BLOWER MOTOR WITH FAN SUB-ASSEMBLY - AUXILIARY BATTERY)


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F10-3 (+B) - Body ground Power switch off 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the F58 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
      F58-6 (BLW) - F10-2 (SI) Always Below 1 Ω
      F58-6 (BLW) or F10-2 (SI) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT BLOWER MOTOR WITH FAN SUB-ASSEMBLY


    1. Reconnect the F10 blower motor with fan sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F58-6 (BLW) - Body ground Always 4.75 to 5.25 V
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY Click here

    OK

  6. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Reconnect the F58 air conditioning amplifier assembly connector.

    2. Turn the power switch on (IG).

    3. Turn the blower switch on (LO).

    4. B004PRBC03
      *a

      Component with harness connected

      (Air Conditioning Amplifier Assembly)

      Connect an oscilloscope to terminals F58-6 (BLW) and F58-4 (GND) of the air conditioning amplifier assembly and check the waveform.

      OK
      Waveform is similar to that shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

      Item Content
      Tool Setting 2 V/DIV., 1 ms./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