LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mitsubishi >> 2005 >> Endeavor LS, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Cruise Control System >> Auto-Cruise Control >> Diagnostic Trouble Code Procedures >> DTC 22: Stoplight Switch System >> Diagnosis
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC 22: Stoplight Switch System: Diagnosis

Required Special Tools: 

  1. STEP 1. Using scan tool MB991958, check data list item 05: Stoplight Switch. 
    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 DIAGNOSTIC FUNCTION  ).
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for auto-cruise control system. (Refer to DIAGNOSTIC FUNCTION  ).
      • Item 05, Stoplight 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".
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is the switch operating properly? 

    1. YES  : Go to Step 2.
    2. NO  : Go to  Step 3.
  2. STEP 2. Using scan tool MB991958, check data list item 06: Brake Switch. 
    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 DIAGNOSTIC FUNCTION  ).
      Fig 1: Connecting Scan Tool To Data Link Connector
      G02393358Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data reading mode for auto-cruise control system. (Refer to DIAGNOSTIC FUNCTION  ).
      • Item 06, Brake Switch.
        • When the brake pedal is depressed, the display on scan tool MB991958 should be "OFF".
        • When the brake pedal is released, the display on scan tool MB991958 should be "ON".
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is the switch operating properly? 

    1. YES  : Go to  Step 21.
    2. NO  : Go to  Step 15.
  3. STEP 3. Check the stoplight operation. 

    Check the stoplight operation.

    • When the brake pedal is depressed, the stoplight will illuminate.
    • When the brake pedal is released, the stoplight does not illuminate.

    Q: Is the stoplight will illuminate (when the brake pedal is depressed) and the stoplight does not illuminate (when the brake pedal is released)? 

    1. YES  : Go to Step 4.
    2. NO  : Go to  Step 8.
  4. STEP 4. Measure the terminal voltage at PCM connector B-18. 
    1. Disconnect all the connectors from the PCM.
      Fig 2: Identifying PCM Connector B-18
      G02393359Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
      Fig 3: Connecting Special Tool MB991923 Between PCM And Body-Side Harness Connector
      G02393360Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Turn the ignition switch to the "ON" position.
    4. Measure the terminal voltage between special tool 18-pin connector terminal 9 (PCM connector B-18 terminal 9) and ground.
      • When the brake pedal is depressed, the voltage should measure battery positive voltage (approximately 12 volts).
      • When the brake pedal is released, the voltage should measure 1 volt or less.
        • Fig 4: Measuring Terminal Voltage Between Special Tool 18-Pin Connector Terminal 9 Ground
        G02393361Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    5. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage battery positive voltage (approximately 12 volts) when the brake pedal is depressed and 1 volt or less when the brake pedal is released? 

    1. YES  : Go to  Step 21.
    2. NO  : Go to Step 5.
  5. STEP 5. Check PCM connector B-18 and joint connector (1) C-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 5: Identifying PCM Connector B-18
    G02393362Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 6: Identifying C-04 Harness Connector
    G02393363Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connector and terminals in good condition? 

    1. YES  : Go to Step 6.
    2. NO  : Repair or replace the damaged components. Refer to HARNESS CONNECTOR INSPECTION . Then go to  Step 22.
  6. STEP 6. Check the harness wire between PCM connector B-18 terminal 9 and joint connector (1) C-04 terminal 6 for damage. 
    Fig 7: Identifying PCM Connector B-18
    G02393364Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 8: Identifying C-04 Harness Connector
    G02393365Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES  : Go to Step 7.
    2. NO  : Repair the damaged harness wire. Then go to  Step 22.
  7. STEP 7. Measure the terminal voltage at PCM connector B-18. 
    1. Disconnect all the connectors from the PCM.
      Fig 9: Identifying B-18 PCM Connector
      G02393366Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
      Fig 10: Connecting Special Tool MB991923 Between PCM And Body-Side Harness Connector
      G02393367Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Turn the ignition switch to the "ON" position.
    4. Measure the terminal voltage between special tool 18-pin connector terminal 9 (PCM connector B-18 terminal 9) and ground.
      • When the brake pedal is depressed, the voltage should measure battery positive voltage (approximately 12 volts).
      • When the brake pedal is released, the voltage should measure 1 volt or less.
        • Fig 11: Measuring Terminal Voltage Between Special Tool 18-Pin Connector Terminal 9 Ground
        G02393368Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    5. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage battery positive voltage (approximately 12 volts) when the brake pedal is depressed and 1 volt or less when the brake pedal is released? 

    1. YES  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Then go to  Step 22.
    2. NO  : Replace the PCM. [Refer to POWER CONTROL MODULE (PCM) ]. Then go to  Step 22.
  8. STEP 8. Measure the power supply voltage at stoplight switch connector C-03 by backprobing. 
    1. Do not disconnect stoplight switch connector C-03.
      Fig 12: Identifying C-03 Harness Connector
      G02393369Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the power supply voltage between stoplight switch connector C-03 terminal 2 and ground by backprobing.
      • When the brake pedal is depressed, the voltage should measure 1 volt or less.
      • When the brake pedal is released, the voltage should measure battery positive voltage (approximately 12 volts).
        Fig 13: Measuring Power Supply Voltage Between Stoplight Switch Connector C-03 Terminal 2 And Ground
        G02393370Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the measured voltage 1 volt or less when the brake pedal is depressed and battery positive voltage (approximately 12 volts) when the brake pedal is released? 

    1. YES  : Go to Step 9.
    2. NO  : Go to  Step 12.
  9. STEP 9. Check stoplight switch connector C-03 and joint connector (1) C-04 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 14: Identifying Stoplight Switch Connector C-03 And Joint Connector C-04
    G02393371Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connector and terminals in good condition? 

    1. YES  : Go to Step 10.
    2. NO  : Repair or replace the damaged components. Refer to HARNESS CONNECTOR INSPECTION . Then go to  Step 22.
  10. STEP 10. Check the harness wire between stoplight switch connector C-03 terminal 1 and joint connector (1) C-04 terminal 11 for damage. 

    Q: Is the harness wire in good condition? 

    1. YES  : Go to Step 11.
    2. NO  : Repair the damaged harness wire. Then go to  Step 22.
      Fig 15: Identifying Stoplight Switch Connector C-03 And Joint Connector C-04
      G02393372Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  11. STEP 11. Check the stoplight switch. 
    1. Remove the stoplight switch. (Refer to BRAKE PEDAL ).
    2. Connect an ohmmeter to the stoplight switch between terminals 1 and 2.
    3. Check for continuity between the terminals when the plunger of the stoplight switch is pushed in, and check for an open circuit when it is released.
      Fig 16: Checking Continuity Between Terminals 1 And 2
      G02393373Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 17: Measuring Plunger Pushing Depth
      G02393374Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. The stoplight switch is operating properly if there is continuity between terminals 1 and 2 when the plunger is pushed in to a depth of within 4.5 mm (0.2 inch) from the outer case edge surface, and if the circuit is open between terminals 1 and 2 when it is released.

    Q: Is the circuit between terminals 1 and 2 still closed even with the plunger pushed in or open when it is released? 

    1. YES  : It can be assumed that this malfunction is intermittent, (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ), and install the stoplight switch. (Refer to BRAKE PEDAL ). Then go to  Step 22.
    2. NO  : Replace the stoplight switch. (Refer to BRAKE PEDAL ). Then go to  Step 22.
  12. STEP 12. Check stoplight switch connector C-03 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 18: Identifying Stoplight Switch Connector C-03
    G02393375Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connector and terminals in good condition? 

    1. YES  : Go to Step 13.
    2. NO  : Repair or replace the damaged components. Refer to HARNESS CONNECTOR INSPECTION . Then go to  Step 22.
  13. STEP 13. Check the harness wire between stoplight switch connector C-03 terminal 2 and relay box for damage. 
    Fig 19: Identifying Stoplight Switch Connector C-03
    G02393376Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES  : Go to Step 14.
    2. NO  : Repair the damaged harness wire. Then go to  Step 22.
  14. STEP 14. Check the fuse number 11 at the relay box in engine compartment. 
    Fig 20: Identifying Fuse Relay Box
    G02393377Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the fuse in good condition? 

    1. YES  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Then go to  Step 22.
    2. NO  : Replace the fuse. Then go to  Step 22.
  15. STEP 15. Measure the terminal voltage at PCM connector B-19. 
    1. Disconnect all the connectors from the PCM.
      Fig 21: Identifying PCM Connector B-19
      G02393378Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
      Fig 22: Connecting Special Tool MB991923 Between PCM And Body-Side Harness Connector
      G02393379Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Turn the ignition switch to the "ON" position.
    4. Measure the terminal voltage between special tool 23-pin connector (without red tape) terminal 33 (PCM connector B-19 terminal 33) and ground.
      • When the brake pedal is depressed, the voltage should measure battery positive voltage (approximately 12 volts).
      • When the brake pedal is released, the voltage should measure 1 volt or less.
        • Fig 23: Measuring Terminal Voltage Between Special Tool 23-Pin Connector Terminal 33 Ground
        G02393380Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    5. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage battery positive voltage (approximately 12 volts) when the brake pedal is depressed and 1 volt or less when the brake pedal is released? 

    1. YES  : Go to  Step 21.
    2. NO  : Go to Step 16.
  16. STEP 16. Check PCM connector B-19 and stoplight switch connector C-03 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 24: Identifying PCM Connector B-19
    G02393381Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 25: Identifying C-03 Harness Connector
    G02393382Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connector and terminals in good condition? 

    1. YES  : Go to Step 17.
    2. NO  : Repair or replace the damaged components. Refer to HARNESS CONNECTOR INSPECTION . Then go to  Step 22.
  17. STEP 17. Check the harness wire between PCM connector B-19 terminal 33 and stoplight switch connector C-03 terminal 3 for damage. 
    Fig 26: Identifying PCM Connector B-19
    G02393383Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 27: Identifying C-03 Harness Connector
    G02393384Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES  : Go to Step 18.
    2. NO  : Repair the damaged harness wire. Then go to  Step 22.
  18. STEP 18. Check the harness wire between stoplight switch connector C-03 terminal 4 and ground for damage. 
    Fig 28: Identifying C-03 Harness Connector
    G02393385Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES  : Go to Step 19.
    2. NO  : Repair the damaged harness wire. Then go to  Step 22.
  19. STEP 19. Check the stoplight switch. 
    1. Remove the stoplight switch (Refer to BRAKE PEDAL ).
    2. Connect an ohmmeter to the stoplight switch between terminals 3 and 4.
      Fig 29: Checking Stoplight Switch Connector
      G02393386Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Check for continuity between the terminals when it is released, and check for an open circuit when the plunger of the stoplight switch is pushed in.
      Fig 30: Measuring Plunger Pushing Depth
      G02393387Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. The stoplight switch is operating properly if there is continuity between terminals 3 and 4 when it is released, and if the circuit is open between terminals 3 and 4 when the plunger is pushed in to a depth of within 4.5 mm (0.2 inch) from the outer case edge surface.

    Q: Is the circuit between terminals 3 and 4 still closed when the plunger is released or open even with it is pushed in? 

    1. YES  : Install the stoplight switch. (Refer to BRAKE PEDAL ). Go to Step 20.
    2. NO  : Replace the stoplight switch. (Refer to BRAKE PEDAL ). Then go to  Step 22.
  20. STEP 20. Measure the terminal voltage at PCM connector B-19. 
    1. Disconnect all the connectors from the PCM.
      Fig 31: Identifying PCM Connector B-19
      G02393388Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Connect special tool MB991923 (check harness) between the PCM and the body-side harness connector.
      Fig 32: Connecting Special Tool MB991923 Between PCM And Body-Side Harness Connector
      G02393389Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Turn the ignition switch to the "ON" position.
    4. Measure the terminal voltage between special tool 23-pin connector (without red tape) terminal 33 (PCM connector B-19 terminal 33) and ground.
      • When the brake pedal is depressed, the voltage should measure battery positive voltage (approximately 12 volts).
      • When the brake pedal is released, the voltage should measure 1 volt or less.
        • Fig 33: Measuring Terminal Voltage Between Special Tool 23-Pin Connector Terminal 33 Ground
        G02393390Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    5. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage battery positive voltage (approximately 12 volts) when the brake pedal is depressed and 1 volt or less when the brake pedal is released? 

    1. YES  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ). Then go to  Step 22.
    2. NO  : Replace the PCM. [Refer to POWER CONTROL MODULE (PCM) ]. Then go to  Step 22.
  21. STEP 21. Using scan tool MB991958, read the diagnostic trouble codes. 
    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 DIAGNOSTIC FUNCTION  ).
      Fig 34: Connecting Scan Tool To Data Link Connector
      G02393391Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to read the diagnostic trouble codes. (Refer to DIAGNOSTIC FUNCTION  ).
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is DTC 22 set? 

    1. YES  : Replace the PCM. [Refer to POWER CONTROL MODULE (PCM) ]. Then go to Step 22.
    2. NO  : It can be assumed that this malfunction is intermittent. (Refer to HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS - HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
  22. STEP 22. Using scan tool MB991958, read the diagnostic trouble codes. 
    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 DIAGNOSTIC FUNCTION  ).
      Fig 35: Connecting Scan Tool To Data Link Connector
      G02393392Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to read the diagnostic trouble codes. (Refer to DIAGNOSTIC FUNCTION  ).
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is DTC 22 set? 

    1. YES  : Return to  Step 1.
    2. NO  : The procedure is complete.
scientia non olet · About LEMON Manuals