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 Initial Inspection and Diagnostic Overview ).
- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
- When the hydraulic unit (integrated with ASC-ECU) is replaced, always perform the calibration of steering wheel sensor, G and yaw rate sensor, brake fluid pressure sensor, cut valve, and inlet valve (Refer to G and Yaw Rate Sensor Calibration , Testing and Inspection , Master Cylinder Brake Fluid Pressure Sensor Calibration , and Testing and Inspection ).

CIRCUIT 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 in ASC-ECU is energized at all times, and the solenoid valve is always energized while the system is in operation unless the initial check is in progress when the ignition switch is turned ON, or unless the periodical system check is in progress.
- ASC-ECU activates the solenoid valve by turning on its driving transistor.

DTC SET CONDITIONS

These diagnostic trouble codes are set under the cases below.

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

PROBABLE CAUSES

ASC-ECU malfunction

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 A
- MB991997: ASC check harness

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

Using scan tool MB991958, diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 3.
NO Repair the CAN bus lines CAN Bus Diagnostics Chart).
After repairing the CAN bus line, go to Step 2.
STEP 2. DTC recheck after repairing the CAN bus line

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

YES Go to Step 3.
NO This diagnosis is complete.
STEP 3. Check whether the DTC 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). Then go to Step 4.
NO Intermittent malfunction How to Cope With Intermittent Malfunctions).
STEP 4. Check whether the DTC is reset.

Erase the DTC.

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

YES Return to Step 1.
NO This diagnosis is complete.