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

DESCRIPTION

The blower motor with fan sub-assembly operates according to signals from the air conditioning amplifier assembly. The blower motor with fan sub-assembly speed signals are transmitted by changes in the duty ratio.

WIRING DIAGRAM

B004610E01
*a from Battery
*b Blower Motor with Fan Sub-Assembly
*c Air Conditioning Amplifier Assembly

CAUTION / NOTICE / HINT

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 ignition switch to ON.

    3. Turn the intelligent tester on.

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

    5. According to the display on the intelligent tester, perform the Active Test.

      Air Conditioner
      Tester Display Test Part Control Range Diagnostic Note
      Blower Motor Blower motor Min.: 0, Max.: 31 -
      OK
      Blower motor with fan sub-assembly operates and blower motor speed changes.

    OK

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

    NG

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


    1. B0046EGE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Blower Motor with Fan Sub-Assembly)

      Disconnect the F36 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
      F36-3 (+B) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F36-1 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the F42 air conditioning amplifier assembly connector.

    2. Disconnect the F36 blower motor with fan sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F42-22 (BLW) - F36-2 (SI) Always Below 1 Ω
      F42-14 (GND) - Body ground Always Below 1 Ω
      F42-22 (BLW) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (BLW SIGNAL)


    1. B0045UFE01
      Text in Illustration
      *a

      Component with harness connected

      (Air Conditioning Amplifier Assembly)

      Remove the air conditioning amplifier assembly Click here.

    2. Reconnect the air conditioning amplifier assembly connector.

    3. Reconnect the blower motor with fan sub-assembly connector.

    4. Using an oscilloscope, check the waveform.

      Measurement Condition
      Item Content
      Terminal No. (Symbol) F42-22 (BLW) - F42-14 (GND)
      Tester Range 1 V/DIV., 500 μs/DIV.
      Condition

      Ignition switch ON

      Blower switch LO
      OK
      Waveform is as shown in the illustration.

      Tech Tips

      Waveform varies with the blower level.


    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

  5. REPLACE BLOWER MOTOR WITH FAN SUB-ASSEMBLY


    1. Replace the blower motor with fan sub-assembly with a new or normally functioning one Click here.

    2. Operate the blower motor with fan sub-assembly to check that it functions properly.

      OK
      Blower motor with fan sub-assembly operates normally.

    OK

    END (BLOWER MOTOR WITH FAN SUB-ASSEMBLY IS FAULTY)

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here