DTC B1A28: Engine Control Module Authenticate Error: 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 to the data link connector.
   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 Tool MB991910 To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Using scan tool MB991958, read the engine control module diagnostic trouble code. 

   Check again if the DTC is set to the engine control module.

   Q: Is the DTC set? 

   YES  : Troubleshoot the MFI system. Refer to MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS for 2.4L engines or MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS for 3.0L engines.

   NO  : Go to  Step 3.

3. STEP 3. Using scan tool MB991958, read the diagnostic trouble code. 

   Check if the DTC is set to the WCM.

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

   Q: Is DTC B1761 or B2206 set other than B1A28? 

   YES  : Perform the troubleshooting for each DTC. Refer to DTC B1761: VIN CODE NOT PROGRAMMED  < B1761> and DTC B2206: VIN CODE MISMATCH  < B2206>.

   NO  : Go to  Step 4.

4. STEP 4. Recheck for diagnostic trouble code. 

   Check again if the DTC is set to the WCM.

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

   Q: Is the DTC set? 

   YES  : Replace WCM and register the ID codes (refer to ID CODES REGISTRATION JUDGMENT TABLE ). Then go to  Step 5.

   NO  : The diagnosis is complete.

5. STEP 5. Recheck for diagnostic trouble code. 

   Check again if the DTC is set to the WCM.

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

   Q: Is the DTC set? 

   YES  : Replace the engine control module and record VIN (refer to HOW TO PERFORM VEHICLE IDENTIFICATION NUMBER (VIN) WRITING ).

   NO  : The procedure is complete.