P1881

DTC P1881: Twin clutch SST control mode switch system (Malfunction)

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.
^ Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

DIAGNOSTIC FUNCTION
TC-SST-ECU checks that the twin clutch SST control mode switch is normal.

DESCRIPTIONS OF MONITOR METHODS
"+" and "-" signals of the twin clutch SST control mode switch is determined to be stuck on.

PROBABLE CAUSES
^ Twin clutch SST control mode switch malfunction
^ Malfunction of TC-SST-ECU

DIAGNOSTIC PROCEDURE

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

STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Repair the CAN bus lines. After repairing the CAN bus line, go to Step 2.

STEP 2. Check whether the DTC is reset.
After 5 or more seconds have passed with the engine idle status, check that the DTC is reset.
Q: Is DTC No. P1881 set?
YES: Go to Step 3.
NO: Intermittent malfunction.

STEP 3. Twin clutch SST control mode switch check
Q: Is the check result normal?
YES: Go to Step 4.
NO: Replace the twin clutch SST control mode switch.

STEP 4. Shift lever assembly replacement
1) Replace the shift lever assembly.
2) Check if the DTC is set.
Q: Is DTC No. P1881 set?
YES: Replace the mechatronic assembly.
NO: Intermittent malfunction.