LIGHTING SYSTEM Power Source Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives IG signals and supplies power to the headlight ECU sub-assemblies via the H-LP relays.

WIRING DIAGRAM

B005PBTE01

CAUTION / NOTICE / HINT

Note


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

  • Before replacing the main body ECU (multiplex network body ECU), refer to Service Bulletin.

  • The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before proceeding with troubleshooting, perform an on-vehicle inspection and confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*

    Click here


    • *: w/o Canister Pump Module with Door Ajar Warning Buzzer Function

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY - POWER SOURCE AND BODY GROUND)


    1. Disconnect the A49 headlight ECU sub-assembly LH connector.

    2. Disconnect the A50 headlight ECU sub-assembly RH connector.

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

      Standard Voltage
      Headlight ECU sub-assembly LH
      Tester Connection Condition Specified Condition
      A49-13 (ECUB) - Body ground Engine switch on (IG) 11 to 14 V
      A49-4 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Headlight ECU sub-assembly RH
      Tester Connection Condition Specified Condition
      A50-13 (ECUB) - Body ground Engine switch on (IG) 11 to 14 V
      A50-4 (IG) - Body ground Engine switch on (IG) 11 to 14 V

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

      Standard Resistance
      Headlight ECU sub-assembly LH
      Tester Connection Condition Specified Condition
      A49-12 (GND) - Body ground Always Below 1 Ω
      Headlight ECU sub-assembly RH
      Tester Connection Condition Specified Condition
      A50-12 (GND) - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG (Headlight ECU Sub-assembly LH) B
      NG (Headlight ECU Sub-assembly RH) C

    A

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

    C

    CHECK HARNESS AND CONNECTOR (POWER SOURCE - H-LP RH RELAY) Click here

    B

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE - H-LP LH RELAY)


    1. Remove the H-LP LH relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Relay terminal 1 - Body ground Always 11 to 14 V
      Relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT H-LP LH RELAY


    1. Inspect the H-LP LH relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE H-LP LH RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (H-LP LH RELAY - HEADLIGHT ECU SUB-ASSEMBLY LH)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - A49-13 (ECUB) Always Below 1 Ω
      Relay terminal 3 or A49-13 (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 (H-LP LH RELAY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 2 - 2C-31 Always Below 1 Ω
      Relay terminal 2 or 2C-31 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

      Click here

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

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

      B005ONCC32
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      2C-31 - MB-15 (HRLY) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

  7. CHECK HARNESS AND CONNECTOR (POWER SOURCE - H-LP RH RELAY)


    1. Remove the H-LP RH relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Relay terminal 1 - Body ground Always 11 to 14 V
      Relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT H-LP RH RELAY


    1. Inspect the H-LP RH relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE H-LP RH RELAY

    OK

  9. CHECK HARNESS AND CONNECTOR (H-LP RH RELAY - HEADLIGHT ECU SUB-ASSEMBLY RH)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 3 - A50-13 (ECUB) Always Below 1 Ω
      Relay terminal 3 or A50-13 (ECUB) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK HARNESS AND CONNECTOR (H-LP RH RELAY - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


    1. Disconnect the J8 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Relay terminal 2 - J8-1 (DIM) Always Below 1 Ω
      Relay terminal 2 or J8-1 (DIM) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR