AIR CONDITIONING SYSTEM Blower Motor Circuit

DESCRIPTION

The blower with fan motor 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

A01CNU9E08
*a from Auxiliary Battery
*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 procedure.

  • When the auxiliary battery is disconnected or the air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.

    Click here

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 with fan motor sub-assembly

      Min.: 0

      Max.: 31

      		 -

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Blower Motor
      OK
      Blower with fan motor sub-assembly operates and changes speed.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

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


    1. Disconnect the I50 air conditioning amplifier assembly connector.

    2. Disconnect the I28 blower with fan motor sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I28-3 (+B) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I28-1 (GND) - Body ground Always Below 1 Ω
      I50-22 (BLW) - I28-2 (SI) Always Below 1 Ω
      I50-22 (BLW) or I28-2 (SI) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK BLOWER WITH FAN MOTOR SUB-ASSEMBLY


    1. A01CP3XC12
      *a

      Rear view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Disconnect the air conditioning amplifier assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I50-22 (BLW) - Body ground Always 4.5 to 5.5 V
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BLOWER WITH FAN MOTOR SUB-ASSEMBLY Click here

    OK

  4. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

    A01CQMJC03
    *a

    Component with harness connected

    (Air Conditioning Amplifier Assembly)

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

      Click here

    2. Turn the power switch on (IG).

    3. Turn the blower switch LO.

    4. Measure the waveform of the air conditioning amplifier assembly connector.

      OK
      Waveform is similar to that shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

      Item Content
      Tester Connection I50-22 (BLW) - I50-14 (GND)
      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 WITH FAN MOTOR SUB-ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here