C104B

DTC C104B Abnormality in FL wheel inlet valve system
DTC C104F Abnormality in FR wheel inlet valve system
DTC C1053 Abnormality in RL wheel inlet valve system
DTC C1057 Abnormality in RR wheel inlet valve system
DTC C105F Abnormality in FL wheel outlet valve system
DTC C1063 Abnormality in FR wheel outlet valve system
DTC C1067 Abnormality in RL wheel outlet valve system
DTC C105B Abnormality in RR wheel outlet valve system
DTC C1200 Abnormality in FL/RR wheel cut valve system
DTC C1204 Abnormality in FR/RL wheel cut valve system
DTC C1208 Abnormality in FL/RR wheel suction valve system
DTC C120C Abnormality in FR/RL wheel suction valve system

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 CAN Bus Line Diagnostics Flow ).
- 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 (Refer to Testing and Inspection , Testing and Inspection and Testing and Inspection ).

OPERATION

- ASC-ECU contains the power supply circuit (terminal No. 32) for the solenoid valve. The solenoid valve is energized by the valve relay, which is incorporated in ASC-ECU.
- The valve relay, which is incorporated in ASC-ECU, is always energizing the solenoid valve unless the initial check is in progress when the ignition switch is turned on, and the recurrent system check is in progress.
- ASC-ECU activates the solenoid valve by turning on its driving transistor.

DTC SET CONDITIONS

These diagnostic trouble codes will be set under the cases below:

- The solenoid valve is not energized even after ASC-ECU has turned on the valve relay (Open circuit is present in the power supply circuit to the ASC-ECU solenoid valve, or the valve relay has failed).
- The solenoid valve is not activated even after ASC-ECU has turned on the valve relay (Open circuit is present in the solenoid valve circuit in ASC-ECU, or the valve relay has failed).
- After ASC-ECU has turned off the driving transistor, the solenoid valve still remains energized (short in the solenoid valve circuit).
- When a solenoid valve failure is detected

PROBABLE CAUSES

- ASC-ECU malfunction

DIAGNOSIS

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.

Use scan tool MB991958 to diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 3.
NO Repair the CAN bus lines Scan Tool Testing and Procedures).
On completion, go to Step 2.
STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines

Erase the DTC.

Q. Are DTC C104B, C104F, C1053, C1057, C105F, C1063, C1067, C105B, C1200, C1204, C1208 or C120C set?

YES Go to Step 3.
NO The procedure is complete.
STEP 3. Check whether the diagnostic trouble code is reset.

Erase the DTC.

Q. Are DTC C104B, C104F, C1053, C1057, C105F, C1063, C1067, C105B, C1200, C1204, C1208 or C120C set?

YES Replace the hydraulic unit (integrated with ASC-ECU) (Refer to Service and Repair).
NO Intermittent malfunction How to Cope With Intermittent Malfunctions).