ASC

DTC C104B,C104F,C1053,C1057/C105F,C1063,C1067,C105B: Abnormality in inlet/ outlet valve (FL,RL,RR,RL)

DTC C1200,C1204/C1208,C120C: Abnormality in cut/suction valve(FL/RR,FR/RL)

Solenoid Valve and Motor Power Supply Circuit:

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.

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, 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, or 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

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. M.U.T.-III CAN bus diagnostics
Use scan tool to diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 3.
NO: Repair the CAN bus lines. On completion, go to Step 2.

STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines
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.
Q: Are DTC C104B, C104F, C1053, C1057, C105F, C1063, C1067, C105B, C1200, C1204, C1208 or C120C set?
YES: Replace the ASC-ECU.
NO: Intermittent malfunction.