COMBUSTION TYPE POWER HEATER SYSTEM Power Heater Switch Circuit

DTC Code DTC Name
Power Heater Switch Circuit

DESCRIPTION

When the heater switch assembly is turned on, the heater assembly sends a drive signal to the heater pump assembly. The heater assembly then receives the fuel necessary for combustion and starts operating.

WIRING DIAGRAM

E267496E01

CAUTION / NOTICE / HINT

Note:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (HEATER SWITCH ASSEMBLY - BATTERY AND BODY GROUND)

    1. E176908C02

      *a

      Front view of wire harness connector

      (to Heater Switch Assembly)

      Disconnect the heater switch assembly connector.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      G1-4 (IG) - Body ground

      Ignition switch ON

      11 to 14 V

      G1-4 (IG) - Body ground

      Ignition switch off

      Below 1 V

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G1-5 (E) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. INSPECT HEATER SWITCH ASSEMBLY

    1. E176907N01

      Remove the heater switch assembly.

    2. Measure the resistance.

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

        Standard Resistance

        Tester Connection

        Switch Condition

        Specified Condition

        4 (IG) - 1 (IN)

        Heater switch assembly ON

        Below 1 Ω

        4 (IG) - 1 (IN)

        Heater switch assembly off

        10 kΩ or higher

    3. Check operation indicator.

      1. Turn the heater switch assembly on.

      2. Connect a positive (+) lead from the battery to terminal 4 (IG) and a negative (-) lead to terminal 5 (E), and check that the operation indicator comes on.

        OK

        Indicator comes on.

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE HEATER SWITCH ASSEMBLY

    OK

  3. CHECK HARNESS AND CONNECTOR (HEATER SWITCH ASSEMBLY - HEATER ASSEMBLY, ENGINE STOP AND START ECU)

    1. Disconnect the G1 heater switch assembly connector.

    2. Disconnect the A33 heater assembly connector.

    3. Disconnect the G87 engine stop and start ECU connector.*

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G1-1 (IN) - A33-3 (IG)

      Always

      Below 1 Ω

      G1-1 (IN) - G87-4 (CHI)*

      Always

      Below 1 Ω

      A33-3 (IG) - Body ground

      Always

      10 kΩ or higher

      G87-4 (CHI) - Body ground*

      Always

      10 kΩ or higher

      *: w/ Stop and Start System

    Result

    Result

    Proceed to

    OK (w/o Stop and Start System)

    A

    OK (w/ Stop and Start System)

    B

    NG

    C
    A

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    B

    REPLACE ENGINE STOP AND START ECU

    Click hereClick hereClick here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR