Inspection Procedure 7: ABS system inoperative



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, Trouble code diagnosis ).

COMMENTS ON TROUBLE SYMPTOM


In case of this trouble symptom, ABS system operation may be disabled. Diagnosis code may be set by the ABS system using M.U.T.-III.

PROBABLE CAUSES



  • Low battery voltage
  • Wiring harness or connector failure of CAN bus line
  • ABS-ECU malfunction

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnosis


Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnosis table ). On completion, go to Step 4.

STEP 2. ABS-ECU power supply circuit check


Refer to .

Q. Is the check result normal?

Go to Step 3.
Repair it and then go to Step 4.

STEP 3. Hydraulic unit check


Refer to .

Q. Is the check result normal?

Go to Step 4.
Repair the brake pipe or replace ABS-ECU (Refer to ).

STEP 4. Operation check


Q. Does ABS operate normally?

The procedure is complete.
Check the brake system related components except the ABS system.