Code No. U1073 Bus-off


caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C, CAN Bus Diagnostics Table).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.

OPERATION

    Signals from the ECUs communicate with the EPS-ECU.

FUNCTION

    The signals from the ECUs communicate with the EPS-ECU for motor control.

TROUBLE JUDGEMENT
Check Conditions
    IG1 voltage: 10 V or more
Judgement Criterion
    The signals from the ECUs cannot communicate (bus off), and the microcomputer determines that there is a problem in the system.
Fail Safe, Back Up Function
    The EPS-ECU displays the electric power steering warning symbol, and stores diagnosis code No. U1073.

PROBABLE CAUSES

  • Malfunction of CAN bus line
  • Malfunction of the EPS-ECU