Wireless Control Module (WCM)

DTC U1412: Implausible vehicle speed signal received

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. (Refer to Trouble Code Diagnosis). CAN Bus Diagnostics Table

TPMS DTC SET CONDITION

WCM receives the wheel speed information from ABS-ECU via the CAN-bus line. If WCM cannot receive the information about the wheel speed sensor from ABS-ECU , this code is set.

TROUBLESHOOTING HINTS
The most likely causes for this DTC to set are:

- Damaged wiring harness and connector
- Malfunction of ABS-ECU
- Malfunction of WCM
- Malfunction of ETACS-ECU

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

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

1. Turn the ignition switch to the "LOCK" (OFF) position.
2. Turn the ignition switch to the "ON" position.
3. Check if the DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the DTC U1412 set?

YES: Go to Step 3.

NO: The procedure is complete.

STEP 3. Check for other diagnostic trouble code.
Check if the diagnostic trouble code is set from ABS-ECU. [Refer to diagnostic trouble code chart] Diagnostic Trouble Code Descriptions

Q: Is the check result normal?

YES: Go to Step 4.

NO: Carry out the troubleshooting for ABS-ECU [Refer to diagnostic trouble code chart]. Diagnostic Trouble Code Descriptions Then go to Step 5.

STEP 4. Check for other diagnostic trouble code.
Check if the diagnostic trouble code is set from ETACS-ECU.
(Refer to diagnostic trouble code chart). Diagnostic Trouble Code Descriptions

Q: Is the check result normal?

YES: Replace the WCM and register ID codes. Then go to Step 5.

NO: Carry out the troubleshooting (Refer to diagnostic trouble code chart). Diagnostic Trouble Code Descriptions Then go to Step 5.

STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.

1. Turn the ignition switch to the "LOCK" (OFF) position.
2. Turn the ignition switch to the "ON" position.
3. Check if the DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the DTC U1412 reset?

YES: Start over at Step 1.

NO: The procedure is complete.