DTC U0168: WCM or KOS-ECU CAN timeout: 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 (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? 

   1. YES:  Go to Step 2.
   2. NO:  Repair the CAN bus line (Refer to DIAGNOSIS ).
      Fig 1: Identifying Data Link Connector And Special Tools

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

   Check if DTC is set to the WCM or KOS-ECU.

   Q: Is the DTC set to the any of the above? 

   1. YES (Set to the WCM.):  Troubleshoot the WCM (Refer to DIAGNOSTIC TROUBLE CODE TABLE ).
   2. YES (Set to the KOS.):  Troubleshoot the KOS (Refer to DIAGNOSTIC TROUBLE CODE TABLE ).
   3. NO (The diagnostic trouble code is not set.):  Go to Step 3.
3. STEP 3. Using scan tool MB991958, read the diagnostic trouble code. 

   Check if the DTC U0168 is set to the combination meter.

   Q: Is the DTC set? 

   1. YES:  Go to Step 4.
   2. NO:  Go to  Step 5.
4. STEP 4. Recheck for diagnostic trouble code. 

   Check again if the DTC is set to the ETACS-ECU.

   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? 

   1. YES:  Replace the WCM or KOS-ECU.
   2. NO:  The trouble can be an intermittent malfunction such as a poor connection or open circuit in the CAN bus lines between the WCM or KOS-ECU and the ETACS-ECU (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
5. STEP 5. Recheck for diagnostic trouble code. 

   Check again if the DTC is set to the ETACS-ECU.

   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? 

   1. YES:  Replace the ETACS-ECU.
   2. NO:  The trouble can be an intermittent malfunction such as a poor connection or open circuit in the CAN bus lines between the WCM or KOS-ECU and the ETACS-ECU (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).