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Home >> Mitsubishi >> 1987 >> Precis Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 16 (Keyless Operation System (Kos) - Lancer Evolution) >> Diagnosis >> Diagnostic Trouble Code Procedures >> DTC B2402: STL unit comm.(system ID); DTC B2403: STL unit comm.(CRC); DTC B2404: STL unit comm.(function code); DTC B2405: STL unit comm.(rolling code); DTC B2406: STL unit comm.(PTC operate); DTC B2407: STL unit comm.(EEPROM); DTC B2408: STL unit comm.(solenoid) >> Diagnosis
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DTC B2402: STL unit comm.(system ID); DTC B2403: STL unit comm.(CRC); DTC B2404: STL unit comm.(function code); DTC B2405: STL unit comm.(rolling code); DTC B2406: STL unit comm.(PTC operate); DTC B2407: STL unit comm.(EEPROM); DTC B2408: STL unit comm.(solenoid): Diagnosis

WARNING: This page is about a different car, the 2008 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

Required Special Tools: 

  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. Fig 1: Connecting Scan Tool To Data Link Connector
      G05395091Courtesy 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. Check key reminder switch connector C-211 and KOS-ECU connector C-05 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Is the key reminder switch connector C-211 and KOS-ECU connector C-05 in good condition? 

    YES  : Go to Step 3.

    NO  : Repair the defective connector.

  3. STEP 3. Wiring harness check between C-211 key reminder switch connector and C-05 KOS-ECU connector for open circuit. 
    1. Disconnect C-211 key reminder switch connector and C-05 KOS-ECU connector.
    2. Measure at the connector side of C-211 key reminder switch connector and C-05 KOS-ECU connector.
    3. Measure the resistance between the terminals.
      • C-211 key reminder switch connector terminal No.9 - C-05 KOS-ECU connector terminal No.5.
        Fig 2: Checking Resistance Between Connector Terminal 9 And 5
        G05395092Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      • C-211 key reminder switch connector terminal No.12 - C-05 KOS-ECU connector terminal No.4.

        OK: Continuity exists (2Ω or less) 

        Fig 3: Checking Resistance Between Connector Terminal 4 And 12
        G05395093Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the check result normal? 

    YES  : Go to Step 4.

    NO (C-211 key reminder switch connector terminal No.9 - C-05 KOS-ECU connector terminal No.5.)  : An open circuit is present in the wiring harness between C-211 key reminder switch connector terminal No. 9 and C-05 KOS-ECU connector terminal No. 5. Repair the wiring harness.

    NO (C-211 key reminder switch connector terminal No.12 - C-05 KOS-ECU connector terminal No.4.)  : An open circuit is present in the wiring harness between C-211 key reminder switch connector terminal No. 12 and C-05 KOS-ECU connector terminal No. 4. Repair the wiring harness.

  4. STEP 4. Check the wiring harness between the C-211 key reminder switch connector (terminal Nos. 9, 12) and the ground for short circuit. 
    1. Disconnect C-211 key reminder switch connector, and check the wiring harness.
    2. Check the wiring harness between C-211 key reminder switch connector (terminal No.9) and ground

      OK: No Continuity 

      Fig 4: Checking Wiring Harness Between C-211 Key Reminder Switch Connector Terminal 9 And Ground
      G05395094Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Check the wiring harness between C-211 key reminder switch connector (terminal No.12) and ground

      OK: No Continuity 

      Fig 5: Checking Wiring Harness Between C-211 Key Reminder Switch Connector Terminal 12 And Ground
      G05395095Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the wiring harness between C-211 key reminder switch connector (terminal No. 9, 12) and the ground in good condition? 

    YES  : Go to Step 5.

    NO (key reminder switch connector C-211 terminal No.9 - ground.)  : Repair the wiring harness between C-211 key reminder switch connector (terminal No. 9) and the ground.

    NO (key reminder switch connector C-211 terminal No.12 - ground.)  : Repair the wiring harness C-211 key reminder switch connector (terminal No. 12) and the ground.

  5. STEP 5. Replace the key reminder switch, and check whether the diagnostic trouble code is reset. 
    1. Erase the DTC.
    2. Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
    3. Check if the DTC is set.

    Q: Is the DTC set? 

    YES  : Replace KOS-ECU and register the ID codes (Refer to ID CODE REGISTRATION NECESSITY JUDGMENT TABLE  ).

    NO  : The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).

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