DTC B1A25: Key ID unmatched: 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

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.
   Fig 1: Connecting Special Tool MB991910 To Data Link Connector
   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   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 ).

2. STEP 2. Register the key ID and recheck the diagnostic trouble code. 

   Register the key ID of the ignition key (refer to ID CODES REGISTRATION JUDGMENT TABLE  ), and recheck if the DTC is set.

   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  : Go to Step 3.

   NO  : The procedure is complete.

3. STEP 3. Replace the ignition key and recheck the diagnostic trouble code. 

   Replace the ignition key by which the DTC is set with the other key, and recheck if the DTC is set.

   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  : Go to Step 4.

   NO  : Go to Step  5.

4. STEP 4. Register the key ID and recheck the diagnostic trouble code. 

   Register the key ID of the ignition key (refer to ID CODES REGISTRATION JUDGMENT TABLE  ), and recheck if the DTC is set.

   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  : Go to Step 5.

   NO  : The procedure is complete.

5. STEP 5. Replace the ignition key and recheck the diagnostic trouble code. 

   Replace the ignition key with a new one, register the key ID and keyless ID of the new key, (refer to ID CODES REGISTRATION JUDGMENT TABLE  ), and recheck if the DTC is set.

   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  ).

   NO  : The procedure is complete.