LIGHTING SYSTEM Power Source Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives IG signals and supplies power to the headlight light control ECU sub-assembly via the H-LP relay.

WIRING DIAGRAM

A01MFO9E06

CAUTION / NOTICE / HINT

Note


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

  • If the main body ECU (multiplex network body ECU) is replaced, refer to Service Bulletin.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY - BATTERY AND BODY GROUND)


    1. A01MHCBC19
      *A Headlight light control ECU sub-assembly LH
      *B Headlight light control ECU sub-assembly RH
      *a

      Front view of wire harness connector

      (Headlight light control ECU sub-assembly)

      Disconnect the A31 headlight light control ECU sub-assembly LH or A30 headlight light control ECU sub-assembly RH connector.

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

      Standard Voltage
      Headlight light control ECU sub-assembly LH
      Tester Connection Switch Condition Specified Condition
      A31-13 (ECUB) - Body ground Headlight on 11 to 14 V
      A31-4 (IG) - Body ground Power switch on (IG) 11 to 14 V
      Headlight light control ECU sub-assembly RH
      Tester Connection Switch Condition Specified Condition
      A30-13 (ECUB) - Body ground Headlight on 11 to 14 V
      A30-4 (IG) - Body ground Power switch on (IG) 11 to 14 V

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

      Standard Resistance
      Headlight light control ECU sub-assembly LH
      Tester Connection Condition Specified Condition
      A31-12 (GND) - Body ground Always Below 1 Ω
      Headlight light control ECU sub-assembly RH
      Tester Connection Condition Specified Condition
      A30-12 (GND) - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (Headlight Light Control ECU Sub-assembly LH) B
      NG (Headlight Light Control ECU Sub-assembly RH) C

    A

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

    C

    CHECK HEADLIGHT RELAY (H-LP-MAIN RH) Click here

    B

  2. INSPECT HEADLIGHT DIMMER RELAY (H-LP-MAIN LH)


    1. Remove the headlight light dimmer relay (H-LP-MAIN LH) from the motor compartment relay block.

    2. Inspect the headlight light dimmer relay (H-LP-MAIN LH).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT DIMMER RELAY (H-LP-MAIN LH)

    OK

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [H-LP-MAIN LH] - BATTERY)


    1. A01MJP0C01
      *a

      Front view of wire harness connector

      (to Headlight Light Dimmer Relay (H-LP-MAIN LH)

      Remove the headlight light dimmer relay (H-LP-MAIN LH) from the motor compartment relay block.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Relay terminal 2 - Body ground Power switch off 11 to 14 V
      Relay terminal 5 - Body ground Power switch off 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [H-LP-MAIN LH] - HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH)


    1. Remove the headlight light dimmer relay (H-LP-MAIN LH) from the motor compartment relay block.

    2. Disconnect the A31 headlight light control ECU LH sub-assembly LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - A31-13 (ECUB) Always Below 1 Ω
      Relay terminal 3 or A31-13 (ECUB) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [H-LP-MAIN LH] - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])


    1. Remove the headlight light dimmer relay (H-LP-MAIN LH) from the motor compartment relay block.

    2. Remove the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

    3. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

    4. Reconnect the 4C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 1 - MB-15 (HRLY) Always Below 1 Ω
      Relay terminal 1 or MB-15 (HRLY) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    B

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    C

    CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [H-LP-MAIN LH] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) Click here

  6. CHECK HEADLIGHT RELAY (H-LP-MAIN RH)


    1. Remove the headlight relay (H-LP-MAIN RH) from the motor compartment relay block.

    2. Inspect the headlight light relay (H-LP-MAIN RH).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE HEADLIGHT RELAY (H-LP-MAIN RH)

    OK

  7. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP-MAIN RH] - BATTERY)


    1. A01MJP0C11
      *a

      Front view of wire harness connector

      (to Headlight Relay (H-LP-MAIN RH))

      Remove the headlight relay (H-LP-MAIN RH) from the motor compartment relay block.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      Relay terminal 2 - Body ground Power switch off 11 to 14 V
      Relay terminal 5 - Body ground Power switch off 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP-MAIN RH RELAY] - HEADLIGHT LIGHT CONTROL ECU ASSEMBLY RH AND MAIN BODY ECU)


    1. Remove the headlight relay (H-LP-MAIN RH) from the motor compartment relay block.

    2. Disconnect the A30 headlight light control ECU RH sub-assembly LH connector.

    3. Disconnect the G6 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - A30-13 (ECUB) Always Below 1 Ω
      Relay terminal 1 - G6-1 (DIM) Always Below 1 Ω
      Relay terminal 3 or A30-13 (ECUB) - Body ground Always 10 kΩ or higher
      Relay terminal 1 or G6-1 (DIM) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    B

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  9. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY [H-LP-MAIN LH] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. Remove the headlight light dimmer relay (H-LP-MAIN LH) from the motor compartment relay block.

    2. Disconnect the 4C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 1 - 4C-29 Always Below 1 Ω
      Relay terminal 1 or 4C-29 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    B

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR