Inspection Procedure 4: ABS warning lamp stays ON after the engine is started.

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.

ABS-ECU sends the illumination request signal of the ABS warning lamp to the combination meter.
ABS-ECU illuminates the ABS warning lamp for approximately 3 seconds for valve check with the ignition switch turned to the "ON" position.

This may be caused by faults in the CAN bus line, combination meter or ABS-ECU.

Damaged wiring harness and connectors
Malfunction of the combination meter
Malfunction of the hydraulic unit assembly (integrated with ABS-ECU)

note Due to the abnormality in the supply voltage, the diagnosis code may not be set even when the ABS warning lamp is illuminated.

DIAGNOSIS PROCEDURE

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

	Go to Step 2.

	Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ). Then go to Step 7.

Use M.U.T.-III to check the diagnosis code for the ABS system.

	Carry out the diagnosis for the diagnosis code (Refer to ).

	Go to Step 3.

Refer to

	Go to Step 4.

	Carry out the diagnosis of ABS-ECU power supply circuit system (Refer to ).

Use M.U.T.-III to check that other diagnosis code is set in the combination meter system.

	Diagnose the combination meter (Refer to GROUP 54A - Troubleshooting ). Then go to Step 7.

	Go to Step 5.

	Go to Step 6.

	NO : Repair the damaged connector. Then go to Step 7.

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting, How to Cope with Intermittent Malfunction ).

	Replace the hydraulic unit assembly (integrated with ABS-ECU) (Refer to ). Then go to Step 7.

	This diagnosis is complete.

	Return to Step 1.