DTC U0100: Engine control module 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)

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 below.
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.
STEP 2. Using scan tool MB991958, read the engine control module diagnostic trouble code.
Check if DTC is set to the engine control module.

Q: Is the DTC set?
1. YES: Troubleshoot the engine (Refer to DIAGNOSTIC TROUBLE CODE TABLE ).
2. NO: Go to STEP 3 below.
STEP 3. Using scan tool MB991958, read the combination meter diagnostic trouble code.
Check if DTC U0100 is set to the combination meter.

Q: Is the DTC set?
1. YES: Go to STEP 4 below.
2. NO: Go to Step 5.
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 engine control module.
2. NO: The trouble can be an intermittent malfunction such as a poor connection or open circuit in the CAN bus lines between the engine control module and the ETACS-ECU (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
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 engine control module and the ETACS-ECU (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).