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

DESCRIPTION

A005JURE01

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

Duty Ratio:

The duty ratio is the ratio of the blower with fan motor sub-assembly on time (T1) to the total of the blower with fan motor sub-assembly on and off time (T2).

The air conditioning amplifier assembly controls the blower with fan motor sub-assembly speed.

WIRING DIAGRAM

A005J08E02
*a from ALT Fuse
*b BLOWER WITH FAN MOTOR 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 (BLOWER MOTOR)


    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 with fan motor 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 WITH FAN MOTOR - BATTERY AND BODY GROUND)


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

    2. A005M2GE01

      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
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Blower with Fan Motor Sub-assembly)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the F42 air conditioning amplifier assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F42-22 (BLW) - F36-2 (SI) Always Below 1 Ω
      F42-14 (GND) - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      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)

    A005JGLE02
    Text in Illustration
    *a

    Component with harness connected

    (Air Conditioning Amplifier Assembly)

    1. Remove the air conditioning amplifier assembly with its connectors still connected Click here.

    2. Using an oscilloscope, check the waveform.

      Measurement Condition
      Item Content
      Terminal No. (Symbol) F42-22 (BLW) - F42-14 (GND)
      Tool Setting 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 WITH FAN MOTOR SUB-ASSEMBLY


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

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

      OK
      Blower with fan motor sub-assembly operates normally.

    OK

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

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here