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Home >> Mitsubishi >> 2012 >> Lancer Evolution MR >> Repair and Diagnosis >> Accessories & Equipment >> Cruise Control Systems >> Cruise Control System - Lancer Evolution >> Cruise Control System Diagnosis >> Diagnostic Trouble Code Procedures >> DTC 22: Stoplight Switch System >> Diagnostic Procedure
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Diagnostic Procedure

Required Special Tools: 

CAUTION: If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code (DTC) may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to TROUBLE CODE DIAGNOSIS ).
  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 (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 (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).

      Q: Is the check result satisfactory? 

      1. YES:  Go to Step 2
      2. NO:  Repair the CAN bus lines (Refer to CAN BUS DIAGNOSTIC CHART ). Then go to Step  16.
        Fig 1: Connecting Scan Tool To Data Link Connector
        G05373979Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  2. STEP 2. Using scan tool MB991958, check data list item 74: Brake light switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
      • Item 74: Brake light switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF".

          Q: Is the switch operating properly? 

          1. YES:  Go to Step  10.
          2. NO:  Go to Step 3.
  3. STEP 3. Using scan tool MB991958, check ETACS system data list item 290: Brake light switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for ETACS system (Refer to DATA LIST REFERENCE TABLE ).
      • Item 290: Brake light switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF".

          Q: Is the switch operating properly? 

          1. YES:  Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) ). Then go to Step  16.
          2. NO:  Go to Step 4.
  4. STEP 4. Check stoplight switch connector C-48, and ETACS-ECU connector C-304 and C-312, for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Refer to HARNESS CONNECTOR INSPECTION .

    Q: Is the connector and terminal in good condition? 

    1. YES:  Go to Step 5.
    2. NO:  Repair or replace the damaged connector. Then go to Step  16.
  5. STEP 5. Check the harness wire between ETACS-ECU connector C-304 terminal number 1 and stoplight switch connector C-48 terminal number 2, and between stoplight switch connector C-48 terminal number 1 and ETACS-ECU connector C-312 terminal number 16, for damage. 
    • Check harness wire for open/short circuit and damage.

      Q: Is the harness wire in good condition? 

      1. YES:  Go to Step 6.
      2. NO:  Repair or replace the damaged harness wire. Then go to Step  16.
  6. STEP 6. Check fuse number 2 at the ETACS-ECU. 

    Q: Is the fuse in good condition? 

    1. YES:  Go to Step 7.
    2. NO:  Check the stoplight system harness and replace the fuse. Then go to Step  16.
      Fig 2: Locating ETACS-ECU Connector
      G05393785Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  7. STEP 7. Check the stoplight switch. 

    Refer to STOPLIGHT SWITCH CHECK .

    Q: Is the stoplight switch operating properly? 

    1. YES:  Go to Step 8.
    2. NO:  Replace the stoplight switch (Refer to BRAKE PEDAL ). Then go to Step  16.
  8. STEP 8. Using scan tool MB991958, check ETACS system data list item 290: Brake light switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for ETACS system (Refer to DATA LIST REFERENCE TABLE ).
      • Item 290: Brake light switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF".

          Q: Is the switch operating properly? 

          1. YES:  Go to Step 9.
          2. NO:  Replace the ETACS-ECU (Refer to ETACS-ECU ). Then go to Step  16.
  9. STEP 9. Using scan tool MB991958, check data list item 74: Brake light switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
      • Item 74: Brake light switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON."
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF."

          Q: Is the switch operating properly? 

          1. YES:  Go to Step 10.
          2. NO:  Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) ). Then go to Step  16.
  10. STEP 10. Using scan tool MB991958, check data list item 89: Normally closed brake switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
      • Item 89: Normally closed brake switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON".
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF".

          Q: Is the switch operating properly? 

          1. YES:  Go to Step  15.
          2. NO:  Go to Step 11.
  11. STEP 11. Check ECM connector B-10 and stoplight switch connector C-48, for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Refer to HARNESS CONNECTOR INSPECTION .

    Q: Is the connector and terminal in good condition? 

    1. YES:  Go to Step 12.
    2. NO:  Repair or replace the damaged connector. Then go to Step  16.
  12. STEP 12. Check the harness wire between ECM connector B-10 terminal number 108 and stoplight switch connector C-48 terminal number 3, and between stoplight switch connector C-48 terminal number 4 and body ground, for damage. 
    • Check harness wire for open/short circuit and damage.

      Q: Is the harness wire in good condition? 

      1. YES:  Go to Step 13.
      2. NO:  Repair or replace the damaged harness wire. Then go to Step  16.
        Fig 3: Locating ETACS-ECU Connector
        G05393786Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  13. STEP 13. Check the stoplight switch. 

    Refer to STOPLIGHT SWITCH CHECK .

    Q: Is the stoplight switch operating properly? 

    1. YES:  Go to Step 14.
    2. NO:  Replace the stoplight switch (Refer to BRAKE PEDAL ). Then go to Step  16.
  14. STEP 14. Using scan tool MB991958, check data list item 89: Normally closed brake switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
      • Item 89: Normally closed brake switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON."
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF."

        Q: Is the switch operating properly? 

        1. YES:  Go to Step 15.
        2. NO:  Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) ). When the ECM is replaced, register the encrypted code (Refer to ID CODE REGISTRATION JUDGMENT TABLE ). Then go to Step  16.
  15. STEP 15. Read the cruise control system DTC. 
    1. Disconnect the negative (-) battery terminal, to erase the DTC of the cruise control system.
    2. Connect the negative (-) battery cable.
    3. Turn the ignition switch to the "ON" position, and press the "ON/OFF" switch to turn the cruise control system to ON (turn on the "CRUISE" indicator light).
    4. With the cruise control switches not operated, depress the brake pedal for several seconds, and then read the DTC of the cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).

      Q: Is DTC 22 set? 

      1. YES:  Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) ). Then go to Step 16.
      2. NO:  It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
  16. STEP 16. Using scan tool MB991958, check data list item 74: Brake light switch and item 89: Normally closed brake switch. 
    1. Connect scan tool MB991958 to the data link connector (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).
      • Item 74: Brake light switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON."
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF."
      • Item 89: Normally closed brake switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "ON."
        • When the brake pedal is released, the display on scan tool MB991958 should be "OFF."

        Q: Is the switch operating properly? 

        1. YES:  Go to Step 17.
        2. NO:  Return to Step  2.
  17. STEP 17. Read the cruise control system DTC. 
    1. Disconnect the negative (-) battery terminal, to erase the DTC of the cruise control system.
    2. Connect the negative (-) battery cable.
    3. Turn the ignition switch to the "ON" position, and press the "ON/OFF" switch to turn the cruise control system to ON (turn on the "CRUISE" indicator light).
    4. With the cruise control switches not operated, depress the brake pedal for several seconds, and then read the DTC of the cruise control system (Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)  ).

      Q: Is DTC 22 set? 

      1. YES:  Return to Step  1.
      2. NO:  The procedure is complete.
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