DTC U1101: CAN Communications System Time Out Error A/T Related Data: Diagnosis

WARNING: This page is about a different car, the 2004 Mitsubishi Galant. However, it is still accessible from the selected car via links, so may be relevant.

Required Special Tools:

MB991958: Scan tool (MUT-III sub assembly)
MB991824: V.C.I.
MB991827: MUT-III USB cable
MB991910: MUT-III main harness A

STEP 1. Using scan tool, diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line. (refer to HOW TO DIAGNOSE THE CAN BUS LINE ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool.
  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 ). Then go to Step 6.
STEP 2. Using scan tool, read the diagnostic trouble code.
CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check for A/T system diagnostic trouble code (Refer to HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODE ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool.
  Q: Is any DTC set?
  1. YES: Repair the automatic transaxle control system. (Refer to DIAGNOSTIC TROUBLE CODE CHART ). Then go to Step 6.
  2. NO: Go to Step 3.
STEP 3. Using scan tool, read the diagnostic trouble code.
CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Check if a DTC, which relates to CAN communication-linked systems below, is set.
  ETACS-ECU
  - DTC 012: Power train control module time-out (related to A/T)
    Combination meter
  - DTC 012: Power train control module time-out (related to A/T)
    Multi-center display
  - DTC 012: Power train control module time-out (related to A/T)
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect scan tool.
  Q: Is DTC 012 set?
  1. YES: Go to Step 4.
  2. NO: Go to Step 5.
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set.

CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Erase the DTC (Refer to HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Turn the ignition switch to the "ON" position.
6. Check if the DTC is set.
7. Turn the ignition switch to the "LOCK" (OFF) position.
8. Disconnect scan tool.
  Q: Is DTC U1101 set?
  1. YES: Replace the PCM [Refer to POWERTRAIN CONTROL MODULE (PCM) ]. Then go to Step 6.
  2. NO: It can be assumed that this malfunction is intermittent. Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .
STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.

CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Erase the DTC (Refer to HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Turn the ignition switch to the "ON" position.
6. Check if the DTC is set.
7. Turn the ignition switch to the "LOCK" (OFF) position.
8. Disconnect scan tool.
  Q: Is DTC U1101 set?
  1. YES: Replace the hydraulic unit (integrated with ABS/TCL-ECU) (Refer to HYDRAULIC UNIT ). Then go to Step 6.
  2. NO: It can be assumed that this malfunction is intermittent. Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS .
STEP 6. Recheck for diagnostic trouble code.
Check again if the DTC is set.

CAUTION: To prevent damage to scan tool, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool.
1. Connect scan tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Erase the DTC (Refer to HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES ).
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Turn the ignition switch to the "ON" position.
6. Check if the DTC is set.
7. Turn the ignition switch to the "LOCK" (OFF) position.
8. Disconnect scan tool.
  Q: Is DTC U1101 set?
  1. YES: Return to Step 1.
  2. NO: The procedure is complete.