Inspection Procedure
1: M.U.T.-III communication with ASC system is impossible.
caution
If there is any
problem in the CAN bus lines, an incorrect diagnosis code may be stored. Prior to this diagnosis,
diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
If the power is supplied with the earth circuit of CAN communication device open
circuited, an electric potential abnormality may occur to the CAN bus lines.
Whenever ECU is replaced, ensure that the CAN bus lines are normal.
When the hydraulic unit (integrated with ASC-ECU) is replaced, always carry out
the calibration of the steering wheel sensor and the G and yaw rate sensor (Refer to and ).
COMMENTS ON TROUBLE SYMPTOM
When M.U.T.-III cannot communicate with the ABS/ASC system, the CAN bus lines,
ASC-ECU power supply circuit system, earth, or ASC-ECU may be faulty.
PROBABLE CAUSES
Damaged wiring harness and connectors
Malfunction of the hydraulic unit assembly (integrated with ASC-ECU)
Wrong routing of M.U.T.-III harness
Abnormality in battery or alternator
Abnormality in power supply voltage to ASC-ECU
ECU malfunction of other system
M.U.T.-III CAN bus diagnosis
Use M.U.T.-III to diagnose the CAN bus lines.
Q.
Is the check result normal?
Check the power supply circuit, and repair if necessary (Refer to ).
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).