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

E323322E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. CONFIRM MODEL

    Result

    Result

    Proceed to

    for Sedan

    A

    for Hatchback, Wagon

    B

    B

    CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - IG POWER SOURCE, BODY GROUND)Click here

    A
  2. CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - IG POWER SOURCE, BODY GROUND)

    1. Disconnect the E97 heater switch assembly connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E97-4 (IG) - Body ground

      Ignition switch ON

      11 to 14 V

      E97-4 (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

      E97-5 (E) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  3. INSPECT HEATER SWITCH ASSEMBLY

    1. E323315C01

      *a

      Component without harness connected

      (Heater Switch Assembly)

      Measure the resistance.

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

        Standard Resistance

        Tester Connection

        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

    2. Check the 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
  4. CHECK HARNESS AND CONNECTOR (HEATER SWITCH ASSEMBLY - HEATER ASSEMBLY, ECM, ENGINE STOP AND START ECU)

    1. Disconnect the A42 heater assembly connector.

    2. Disconnect the E24 engine stop and start ECU connector.*1

    3. Disconnect the A101*3 or A169*4 ECM connector.*2

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E97-1 (IN) - A42-3 (IG)

      Always

      Below 1 Ω

      E97-1 (IN) - E24-4 (CHI)*1

      Always

      Below 1 Ω

      E97-1 (IN) - A101-26 (MHSW)*2, *3

      Always

      Below 1 Ω

      E97-1 (IN) - A169-32 (MHSW)*2, *4

      Always

      Below 1 Ω

      A42-3 (IG) - Body ground

      Always

      10 kΩ or higher

      E24-4 (CHI) - Body ground*1

      Always

      10 kΩ or higher

      A101-26 (MHSW) - Body ground*2, *3

      Always

      10 kΩ or higher

      A169-32 (MHSW) - Body ground*2, *4

      Always

      10 kΩ or higher

      • *1: w/ Stop and Start System

      • *2: for 1ND-TV

      • *3: w/o Glow Plug Controller

      • *4: w/ Glow Plug Controller

    Result

    Result

    Proceed to

    OK (Resistance between heater assembly and heater switch assembly is normal)

    A

    OK (Resistance between heater assembly and ECM is normal)

    B

    OK (Resistance between heater assembly and engine stop and start ECU is normal)

    C

    NG

    D

    A

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    B

    REPLACE ECM

    w/o Glow Plug Controller:Click here

    w/ Glow Plug Controller:Click here

    C

    REPLACE ENGINE STOP AND START ECU

    D

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - IG POWER SOURCE, BODY GROUND)

    1. Disconnect the E135 heater switch assembly connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E135-8 (IG) - Body ground

      Ignition switch ON

      11 to 14 V

      E135-8 (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

      E135-3 (E) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK
  6. INSPECT HEATER SWITCH ASSEMBLY

    1. E323316C01

      *a

      Component without harness connected

      (Heater Switch Assembly)

      Measure the resistance.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        8 (IG) - 5 (IN)

        Heater switch assembly: On

        Below 1 Ω

        8 (IG) - 5 (IN)

        Heater switch assembly: Off

        10 kΩ or higher

    2. Check the operation indicator.

      1. Turn the heater switch assembly on.

      2. Connect a positive (+) lead from the battery to terminal 8 (IG) and a negative (-) lead to terminal 3 (E), and check that the operation indicator comes on.

        OK

        Indicator comes on.

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE HEATER SWITCH ASSEMBLY

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

    1. Disconnect the A42 heater assembly connector.

    2. Disconnect the E24 engine stop and start ECU connector.*1

    3. Disconnect the A169 ECM connector.*2

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E135-5 (IN) - A42-3 (IG)

      Always

      Below 1 Ω

      E135-5 (IN) - E24-4 (CHI)*1

      Always

      Below 1 Ω

      E135-5 (IN) - A169-32 (MHSW)*2

      Always

      Below 1 Ω

      A42-3 (IG) - Body ground

      Always

      10 kΩ or higher

      E24-4 (CHI) - Body ground*1

      Always

      10 kΩ or higher

      A169-32 (MHSW) - Body ground*2

      Always

      10 kΩ or higher

      • *1: w/ Stop and Start System

      • *2: for 1ND-TV

    Result

    Result

    Proceed to

    OK (Resistance between heater assembly and heater switch assembly is normal)

    A

    OK (Resistance between heater assembly and ECM is normal)

    B

    OK (Resistance between heater assembly and engine stop and start ECU is normal)

    C

    NG

    D

    A

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    B

    REPLACE ECM

    C

    REPLACE ENGINE STOP AND START ECU

    D

    REPAIR OR REPLACE HARNESS OR CONNECTOR