COMBUSTION TYPE POWER HEATER SYSTEM Power Heater Fuel Pump Circuit

DESCRIPTION

When the heater switch assembly (power heater switch) is turned on, the heater pump assembly receives a drive voltage from the heater assembly. The heater pump assembly provides the heater assembly with fuel necessary for combustion, allowing the heater assembly to operate.

WIRING DIAGRAM

A01XG1GE03
*a Heater Pump Assembly
*b Heater Assembly

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (HEATER ASSEMBLY - HEATER PUMP ASSEMBLY)


    1. Disconnect the A97 heater assembly connector.

    2. Disconnect the A96 heater pump assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A97-2 (L) - A96-1 (B2) Always Below 1 Ω
      A97-2 (L) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (HEATER PUMP ASSEMBLY - BODY GROUND)


    1. A01XCAIE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Heater Pump Assembly)

      Disconnect the heater pump assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A96-1 (E2) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT HEATER PUMP ASSEMBLY


    1. A01XIICE13

      Remove the heater pump assembly Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (B2) - 1 (E2) Always 9 to 12 Ω

    3. Inspect heater pump assembly operation.


      1. Connect a positive (+) lead from the battery to terminal 2 (B2) and a negative (-) lead to terminal 1 (E2), and check the pressure of the hose by hand.

        Note

        This inspection must be done quickly (within 10 seconds) to prevent damage to the heater pump assembly.

      Result
      Result Proceed to
      The pressure is applied to the hose A
      The pressure is not applied to the hose B

    B

    REPLACE HEATER PUMP ASSEMBLY Click here

    A

  4. CHECK HEATER ASSEMBLY


    1. A01XD1EE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Heater Pump Assembly)

      Disconnect the heater pump assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A96-2 (B2) - Body ground Engine running, heater switch assembly (power heater switch) on 11 to 14 V
      A96-2 (B2) - Body ground Engine running, heater switch assembly (power heater switch) off Below 1 V

    OK

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

    NG

    REPLACE HEATER ASSEMBLY Click here