CAN COMMUNICATION SYSTEM (for LHD), Diagnostic DTC:U0141

DTC Code DTC Name
U0141 Lost Communication with Body Control Module "A"

DESCRIPTION

DTC Code DTC Detection Condition Trouble Area
U0141 There is no communication from the No. 2 main body ECU.

  • Power source circuit of No. 2 main body ECU

  • No. 2 main body ECU CAN branch wire or connector

  • No. 2 main body ECU

WIRING DIAGRAM

A01EONSE01

INSPECTION PROCEDURE

Note

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

Tech Tips

Operating the engine switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. PRECAUTION

    Note

    After turning the engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.


    NEXT

  2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.


    NEXT

  3. CHECK FOR OPEN IN CAN BUS WIRE (REAR JUNCTION BLOCK CAN BRANCH WIRE)


    1. A01EQYRE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 2 Main Body ECU)

      Disconnect the L33 No. 2 main body ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L33-11 (MPX+) - L33-12 (MPX-) Engine switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE NO. 2 MAIN BODY ECU CAN BRANCH WIRE OR CONNECTOR (MPX+, MPX-)

    OK

  4. CHECK HARNESS AND CONNECTOR (NO. 2 MAIN BODY ECU - BATTERY AND BODY GROUND)


    1. A01EQYRE02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to No. 2 Main Body ECU)

      Connect the cable to the negative (-) battery terminal.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      L33-14 (BECU) - Body ground Always 11 to 14 V
      L33-13 (SIG) - Body ground Engine switch on (IG) 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L33-7 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE NO. 2 MAIN BODY ECU Click here