COMBUSTION TYPE POWER HEATER SYSTEM Power Heater Alternator Circuit

DESCRIPTION

The ECU receives engine operation signals from the L terminal of the generator assembly. If this circuit is open, the ECU will determine that the engine operation signals indicate that the engine is running. If this circuit is shorted, the ECU will determine that the engine operation signals indicate that the engine is stopped, and the heater assembly will not operate.

WIRING DIAGRAM

A004O4FE01

PROCEDURE


  1. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY


    1. Remove the generator assembly.


    2. A004QQD

      Using a vernier caliper, measure the brush length.

      Standard exposed length
      10.5 to 11.5 mm (0.374 to 0.453 in.)
      Minimum exposed length
      4.5 mm (0.177 in.)

    NG

    REPLACE GENERATOR BRUSH HOLDER ASSEMBLY Click here

    OK

  2. INSPECT GENERATOR ROTOR ASSEMBLY


    1. Remove the generator assembly.


    2. Check the rotor for an open circuit.


      1. A004SZSE04
        Text in Illustration
        *1 Slip Ring

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Slip ring - Slip ring 20°C (68°F) 2.3 to 2.7 Ω

    3. Check if the rotor is grounded.


      1. A004Q9SE05
        Text in Illustration
        *1 Slip Ring
        *2 Rotor Core

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        Slip ring - Rotor Always 10 kΩ or higher

    4. Check that the slip rings are not rough or scored.

    5. A004QVS

      Using a vernier caliper, measure the slip ring diameter.

      Standard diameter
      14.2 to 14.4 mm (0.559 to 0.567 in.)
      Minimum diameter
      14.0 mm (0.551 in.)
    6. A004S7S

      Check that the generator rotor bearing is not rough or worn, and that it rotates smoothly.

      OK
      The results are as specified.

    NG

    REPLACE GENERATOR ROTOR ASSEMBLY Click here

    OK

  3. INSPECT GENERATOR DRIVE END FRAME BEARING


    1. Remove the generator assembly.


    2. A004SCE

      Check that the generator drive end frame bearing is not rough or worn, and that it rotates smoothly.

      OK
      The generator drive end frame bearing is normal.

    NG

    REPLACE GENERATOR DRIVE END FRAME BEARING Click here

    OK

  4. INSPECT GENERATOR PULLEY


    1. Remove the generator assembly.


    2. A004MM7E02
      Text in Illustration
      *1 Free
      *2 Lock

      Hold the center of the generator pulley and confirm that the outer ring turns counterclockwise and does not turn clockwise.

      OK
      The generator pulley is normal.

    NG

    REPLACE GENERATOR PULLEY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - GENERATOR)


    1. A004O0OE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Heater Assembly)
      *2

      Front view of wire harness connector

      (to Generator Assembly)

      Disconnect the A54 heater assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A54-8 (+) - Body ground

      Engine running

      (Generator operating)

      		 11 to 14 V

    3. Disconnect the B16 generator assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A54-8 (+) - B16-4 (L) Always Below 1 Ω
      A54-8 (+) - Body ground Always 10 kΩ or higher

    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. REPLACE GENERATOR BRUSH HOLDER ASSEMBLY


    1. Replace the generator brush holder assembly.



    NEXT

    END

  7. REPLACE GENERATOR ROTOR ASSEMBLY


    1. Replace the generator rotor assembly.



    NEXT

    END

  8. REPLACE GENERATOR DRIVE END FRAME BEARING


    1. Replace the generator drive end frame bearing.



    NEXT

    END

  9. REPLACE GENERATOR PULLEY


    1. Replace the generator pulley.



    NEXT

    END