DTC U0168: WCM CAN timeout: Diagnosis

Required Special Tools: 

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: Vehicles Communication Interface (V.C.I.).
  • MB991827: M.U.T.-III USB Cable
  • MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. STEP 1. Using scan tool MB991958, diagnose the CAN bus line. 
   CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
   1. Connect scan tool MB991958. Refer to "HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ".
   2. Turn the ignition switch to the "ON" position.
   3. Diagnose the CAN bus line.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the CAN bus line found to be normal? 

   YES:  Go to Step 2.

   NO:  Repair the CAN bus line (Refer to DIAGNOSIS ).

   Fig 1: Connecting Special Tools To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Using scan tool MB991958, read the KOS-ECU < vehicles with KOS > or WCM < vehicles with WCM > diagnostic trouble code. 

   Check again if the DTC is set to the KOS-ECU < vehicles with KOS > or WCM < vehicles with WCM >.

   Q: Is the DTC set? 

   YES:  Troubleshoot the KOS or WCM (Refer to DIAGNOSTIC TROUBLE CODE CHART < KOS > or DIAGNOSTIC TROUBLE CODE CHART < WCM >).

   NO:  Go to Step 3.

3. STEP 3. Recheck for diagnostic trouble code. 

   Check again if the DTC is set to the radio and CD player or CD changer.

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

   Q: Is the DTC set? 

   YES:  Replace the radio and CD player or CD changer.

   NO:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).