POWER DOOR LOCK CONTROL SYSTEM Power Source Circuit

DTC Code DTC Name
Power Source Circuit

DESCRIPTION

The main power source for the main body ECU (multiplex network body ECU) is supplied via the door control battery.

WIRING DIAGRAM

B375840E05

CAUTION / NOTICE / HINT

Note:

  • When replacing the main body ECU (multiplex network body ECU), make sure to replace it with a new one.

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.

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

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (DOOR CONTROL BATTERY - BATTERY AND BODY GROUND)

    1. B377768C23

      *a

      Front view of wire harness connector

      (to Door Control Battery)

      Disconnect the door control battery connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      N37-4 (BECU) - Body ground

      Always

      11 to 14 V

      N37-5 (BATB) - Body ground

      Always

      11 to 14 V

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      N37-2 (GND1) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (DOOR CONTROL BATTERY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

    1. Disconnect the N37 door control battery connector.

    2. Disconnect the 3D 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

      N37-3 (EDOR) - 3D-41

      Always

      Below 1 Ω

      N37-3 (EDOR) or 3D-41 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    1. Remove the instrument panel junction block assembly.

    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.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A-30 (BECU) - 3D-41

      Always

      Below 1 Ω
    B375843C10

    *a

    Component without harness connected

    (Instrument Panel Junction Block Assembly)

    -

    -

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    OK

  4. INSPECT DOOR CONTROL BATTERY (POWER OUTPUT)

    1. Turn the engine switch off.

    2. Remove the ECU-B NO. 1 fuse from the engine room relay block. and leave the vehicle as is for 50 minutes.

    3. Leave the vehicle as is for 30 minutes (wait until the door control battery is discharged).

      Tip:

      Discharge time is reduced when the door control battery is not fully charged.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      N37-3 (EDOR) - Body ground

      Engine switch off

      Below 2 V

    5. Install the ECU-B NO.1 fuse to the engine room relay block.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      N37-3 (EDOR) - Body ground

      Engine switch off

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    NG

    REPLACE DOOR CONTROL BATTERY

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