Inspection Procedure 1: The M.U.T.-III cannot communicate with the TCL/ASC system.


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.
  • Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
  • If the power is supplied with the earth circuit of CAN communication devices open circuited, a potential abnormality may occur to the connected CAN bus line.
  • When the hydraulic unit (integrated with TCL/ASC-ECU) is replaced, always perform the calibration of steering wheel sensor. (Refer to .)

TECHNICAL DESCRIPTION (COMMENT)
When the M.U.T.-III cannot communicate with the TCL/ASC system, there may be a malfunction to the CAN bus lines, TCL/ASC-ECU power supply circuit system, earth, or TCL/ASC-ECU.

PROBABLE CAUSES

  • Damaged wiring harness and connectors
  • TCL/ASC-ECU malfunction
  • Wrong M.U.T.-III wiring harness
  • Abnormality in battery or alternator
  • Abnormality in power supply voltage to TCL/ASC-ECU
  • ECU malfunction of other system

DIAGNOSIS

Using M.U.T.-III, diagnose the CAN bus lines.
Using the M.U.T.-III, diagnose the CAN bus lines.

Q. Is the check result normal?
Check and repair the power supply circuit system. ( Refer to .)
Repair the CAN bus lines. (Refer to GROUP 54C - Troubleshooting .)