Inspection Procedure 11: ASC System Does Not Operate or Faulty ASC Operate

Inspection Procedure 11: ASC System does not Operate or Faulty ASC Operate.

CAUTION:
^ If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose 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, the G and yaw rate sensor and brake fluid pressure sensor.

COMMENTS ON TROUBLE SYMPTOM
In case of this trouble symptom, ASC system operation may be disabled. Diagnostic trouble code may be set by the TCL/ASC system using scan tool.

PROBABLE CAUSES
^ Low battery output
^ Wring harness or connector failure of CAN bus line
^ ASC-ECU malfunction
^ Different ETACS-ECU, abnormal variant coding information

DIAGNOSIS

Required Special Tools:
^ MB991958: Scan Tool (M.U.T.-III Sub Assembly)
^ MB991824: Vehicle Communication Interface (V.C.I.)
^ MB991827: M.U.T.-III USB Cable
^ MB991910: M.U.T.-III Main Harness

STEP 1. M.U.T.-III diagnostic trouble code check
Q: Is the check result normal?
YES: Go to Step 2.
NO: Troubleshoot for the relevant diagnostic trouble code.

STEP 2. Check the ASC-ECU power supply circuit system.
Refer to Inspection Procedure 12: ASC-ECU Power Supply Circuit System. Inspection Procedure 12: ASC-ECU Power Supply Circuit System
Q: Is the check result normal?
YES: Go to Step 3.
NO: Diagnose the power supply circuit of the ASC-ECU.

STEP 3. ETACS-ECU coding data check
Q: Is the check result normal?
YES: Go to Step 4.
NO: Replace the ETACS-ECU.

STEP 4. Actuator test operation check
Q: Is the check result normal?
YES: Go to Step 5.
NO: Replace the ASC-ECU.

STEP 5. Wheel speed sensor, steering wheel sensor and G and yaw rate sensor check
Q: Is the check result normal?
YES: Go to Step 6.
NO: Repair or replace it.

STEP 6. Hydraulic unit (integrated with ASC-ECU) check
Check that the brake tube is installed to the hydraulic unit (integrated with ASC-ECU) correctly.
Q: Is the check result normal?
YES: Replace the ASC-ECU. Then go to Step 7.
NO: Connect the brake tubes correctly, and repair or replace the external brake lines of the hydraulic unit (integrated with ASC-ECU).

STEP 7. Operation check
Q: Does ASC operate normally?
YES: This diagnosis is complete.
NO: Check the brake system related components except the ASC system.