CAN COMMUNICATION SYSTEM Seat Belt Control ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Seat Belt Control ECU Communication Stop Mode

  • "Pre-crash Seat Belt" is not displayed on the "Communication Bus Check" screen of the intelligent tester

  • Applies to "Seat Belt Control ECU Communication Stop Mode" in the "DTC COMBINATION TABLE"

  • Power source circuit of the seat belt control ECU

  • Seat belt control ECU branch line or connector

  • Seat belt control ECU

Tech Tips

"Pre-crash Seat Belt" refers to the circuit that includes the seat belt control ECU.

WIRING DIAGRAM

A0163AWE10
A0163K3E01

INSPECTION PROCEDURE

Note


  • Turn the engine switch off before measuring the resistance of CAN bus main wires and CAN bus branch wires.

  • After the engine switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the engine switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

Tech Tips

Operating the engine switch, any switches, or any doors triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.

PROCEDURE


  1. CHECK OPEN IN CAN BUS WIRE (SEAT BELT CONTROL ECU BRANCH LINE)


    1. Turn the engine switch off.

    2. Disconnect the seat belt control ECU connector (Q38).

    3. A0163CEE18

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

      Standard Resistance
      Tester Connection Switch Condition Specified Value
      Q38-4 (CANH) - Q38-6 (CANL) Engine switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE SEAT BELT CONTROL ECU BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)

    OK

  2. CHECK WIRE HARNESS (IG1, PGND)


    1. A0163CEE19

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

      Standard Resistance
      Tester Connection Condition Specified Value
      Q38-18 (PGND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Value
      Q38-3 (IG1) - Body ground Engine switch on (IG) 10 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE SEAT BELT CONTROL ECU Click here