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Home >> Mitsubishi >> 2004 >> Lancer Evolution >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 40 (Auto-Cruise Control System - 2.4L (Except Evolution & SPORTBACK)) >> Auto-Cruise Control System Diagnosis >> Diagnostic Trouble Code Procedures >> DTC 15: Auto-cruise Control Switch System >> Diagnosis
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DTC 15: Auto-cruise Control Switch System: Diagnosis

WARNING: This page is about a different variant/trim than selected.

Required Special Tools: 

  1. STEP 1. Using scan tool MB991958, check data list item 01: Main Switch, list item 02: Set Switch, item 03: Resume Switch and list item 04: Cancel 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 AUTO-CRUISE CONTROL SYSTEM DIAGNOSTIC FUNCTION ).
      Fig 1: Connecting Scan Tool MB991958 To Data Link Connector
      G00809720Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991958 to data list mode.
      • Item 01: Main Switch.
        • When "CRUISE" (MAIN) switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
        • When "CRUISE" (MAIN) switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
    4. Set scan tool MB991958 to data list mode.
      • Item 02: Set Switch.
        • When "COAST/SET" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
        • When "COAST/SET" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
    5. Set scan tool MB991958 to data list mode.
      • Item 03: Resume Switch.
        • When "ACC/RES" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
        • When "ACC/RES" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
    6. Set scan tool MB991958 to data list mode.
      • Item 04: Cancel Switch.
        • When "CANCEL" switch is at the "ON" position, the display on scan tool MB991958 should be "ON".
        • When "ACC/RES" switch is at the "OFF" position, the display on scan tool MB991958 should be "OFF".
    7. Turn the ignition switch to the "LOCK" (OFF) position.
    8. Disconnect scan tool MB991958.

    Q: Is the switch operating properly? 

    1. YES:  Go to  Step 17.
    2. NO:  Go to Step 2.
  2. STEP 2. Measure the power supply voltage at auto-cruise control switch connector C-202 by backprobing. 
    1. Remove the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ).
    2. Connect the negative (-) battery cable.
    3. Do not disconnect auto-cruise control switch connector C-202.
      Fig 2: Identifying Connector C-202
      G00809721Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
    5. Measure the voltage between connector C-202 terminal 2 and ground by backprobing.
      • The voltage should be between 4.7 and 5.0 volts.
        • Fig 3: Measuring Voltage Between Connector C-202 and Ground
        G00809722Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    6. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 4.7 and 5.0 volts? 

    1. YES:  Go to  Step 9.
    2. NO:  Go to Step 3.
  3. STEP 3. Measure the power supply voltage at ECM connector C-139 < M/T > or PCM connector C-140 < A/T > by backprobing. 
    1. Do not disconnect ECM connector C-139 < M/T > or PCM connector C-140 < A/T >.
      Fig 4: Identifying Connectors: C-139, C-140
      G00809723Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
    3. Measure the voltage between ECM connector C-139 < M/T > terminal 94 or PCM connector C-140 < A/T > terminal 94 and ground by backprobing.
      • The measured voltage should be between 4.7 and 5.0 volts.
        • Fig 5: Measuring Voltage Between ECM Connector C-139 (M/T) or PCM Connector C-140 (A/T) and Groun
        G00809724Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 4.7 and 5.0 volts? 

    1. YES:  Go to  Step 6.
    2. NO:  Go to Step 4.
  4. STEP 4. Check ECM connector C-139 < M/T > or PCM connector C-140 < A/T > for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 6: Identifying Connectors: C-139, C-140
    G00809725Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the connector and terminals in good condition? 

    1. YES:  Go to Step 5.
    2. NO:  Repair or replace the faulty connector and install the air bag module (driver's side). (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  5. STEP 5. Check the harness for short circuit to ground between the ECM connector C-139 < M/T > terminal 94 or PCM connector C-140 < A/T > terminal 94 and the auto-cruise control switch connector C-202 terminal 2. 
    1. Disconnect ECM connector C-139 < M/Y > or PCM connector C-140 and measure at the harness connector side.
      Fig 7: Identifying Connector C-139, C-140
      G00809726Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "OFF" position.
    3. Measure the continuity between ECM connector C-139 < M/T > terminal 94 or PCM connector C-140 < A/T > terminal 94 and ground.
      Fig 8: Measuring Continuity Between ECM Connector C-139 (M/T) Or PCM Connector C-140 and Ground
      G00809727Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Connect ECM connector C-139 < M/T > or PCM connector C-111 < A/T >.

    Q: Is the measured continuity open circuit? 

    1. YES:  Install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 17.
    2. NO:  Go to Step 6.
  6. STEP 6. Check auto-cruise control switch connector C-202, intermediate connector C-229-1 and C-108 and clock spring connectors C-204 and C-229 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 9: Identifying Connectors: C-202, C-204, C-229, C-229-1
    G00809728Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 10: Identifying Connector C-108
    G00809729Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are there connectors and terminals in good condition? 

    1. YES:  Go to Step 7.
    2. NO:  Repair or replace the faulty connector and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  7. STEP 7. Check the harness wire between ECM connector C-139 < M/T > terminal 94 or PCM connector C-104 < A/T > terminal 94 and auto-cruise control switch connector C-202 terminal 2 for damage. 
    Fig 11: Identifying Connector C-139 (M/T) and C-104
    G00809730Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 12: Identifying Connector C-202
    G00809731Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are there harness wires in good condition? 

    1. YES:  Go to Step 8.
    2. NO:  Repair the damaged harness wire, and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  8. STEP 8. Check the clock spring. 

    Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING .

    Q: Is the clock spring in good condition? 

    1. YES:  It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS , and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
    2. NO:  Replace the clock spring and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  9. STEP 9. Measure the ground voltage at auto-cruise control switch connector C-202 by backprobing. 
    1. Do not disconnect auto-cruise control switch connector C-202.
      Fig 13: Identifying Connector C-202
      G00809732Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "ON" position.
    3. Measure the voltage between connector C-202 terminal 3 and ground.
      • The measured voltage should be 0.5 volt or less.
        Fig 14: Measuring Voltage Between Connector C-202 and Ground
        G00809733Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the "CRUISE" (MAIN) switch to the "OFF" position and the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage 0.5 volt or less? 

    1. YES:  Go to  Step 15.
    2. NO:  Go to Step 10.
  10. STEP 10. Measure the ground voltage at ECM connector C-141 < M/T > or PCM connector C-142 < A/T > by backprobing. 
    1. Do not the disconnect ECM connector C-141 < M/T > or PCM connector C-142 < A/T >.
      Fig 15: Identifying ECM Connector C-141 (M/T) or PCM Connector C-142 (A/T)
      G00809734Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position and the "CRUISE" (MAIN) switch to the "ON" position.
    3. Measure the voltage between ECM connector C-141 < M/T > or PCM connector C-142 < A/T > terminal 146 and ground by backprobing.
      • The measured voltage should be 0.5 volt or less.
        Fig 16: Measuring Voltage Between Connector C-141 or C-142 Terminal 146 and Ground
        G00809735Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the "CRUISE" (MAIN) switch to the "OFF" position and the ignition switch to the "OFF" position.

    Q: Is the measured voltage 0.5 volt or less? 

    1. YES:  Go to  Step 12.
    2. NO:  Go to Step 11.
  11. STEP 11. Check ECM connector C-141 < M/T > or PCM connector C-142 < A/T > for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 17: Identifying Connectors: C-141 (M/T), C-142 (A/T)
    G00809736Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the connector and terminals in good condition? 

    1. YES:  Install-the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 17.
    2. NO:  Repair or replace the faulty connector and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  12. STEP 12. Check ECM connector C-141 < M/T > or PCM connector C-142 < A/T >, intermediate connector C-108 and C-229-1, auto-cruise control switch connector C-202 and clock spring connectors C-204 and C-229 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 18: Identifying Connectors: C-141 (M/T), C-142 (A/T)
    G00809737Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 19: Identifying Connector C-108
    G00809738Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 20: Identifying Connectors C-202, C-204, C229, C-229-1
    G00809739Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are there connectors and terminals in good condition? 

    1. YES:  Go to Step 13.
    2. NO:  Repair or replace the faulty connector and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  13. STEP 13. Check the harness wire between ECM connector C-141 < M/T > terminal 146 or PCM connector C-142 < A/T > terminal 146 and auto-cruise control switch connector C-202 terminal 3 for damage. 
    Fig 21: Identifing ECM Connector C-141 (M/T) and C-143 (A/T)
    G00809740Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 22: Identifying Connector C-202
    G00809741Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are there harness wires in good condition? 

    1. YES:  Go to Step 14.
    2. NO:  Repair the damaged harness wire, and install the air bag module (driver's side). (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  14. STEP 14. Check the clock spring. 

    Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING .

    Q: Is the clock spring in good condition? 

    1. YES:  It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS , and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
    2. NO:  Replace the clock spring and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  15. STEP 15. Check auto-cruise control switch connector C-202 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 23: Checking Connector C-202
    G00809742Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the connector and terminals in good condition? 

    1. YES:  Go to Step 16.
    2. NO:  Repair or replace the faulty connector and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  16. STEP 16. Check the auto-cruise control switch. 
    1. Remove auto-cruise control switch. (Refer to P.17-204).
    2. Measure the resistance between terminal 2 and terminal 3 when each of the "CRUISE" (MAIN), "COAST/SET", "ACC/RES" and "CANCEL" switch is pressed.
      Fig 24: Measuring Resistance
      G00809744Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 25: Identifying Switch Positions & Conditions
      G00809743Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the resistance within specifications? 

    1. YES:  Install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to Step 17.
    2. NO:  Replace the auto-cruise control switch (Refer to AUTO-CRUISE CONTROL ), and install the air bag module (driver's side) (Refer to DRIVER-SIDE AIR BAG MODULE & CLOCKSPRING ). Then go to  Step 18.
  17. STEP 17. Using scan tool MB991958, read the diagnostic trouble code. 
    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 (MUT-III). ).
      Fig 26: Connecting Scan Tool MB991958 To Data Link Connector
      G00809745Courtesy 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.
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is DTC 15 set? 

    1. YES:  Replace the ECM < M/T > or PCM < A/T > [Refer to ENGINE CONTROL MODULE (ECM) AND POWERTRAIN CO ]. Then go to Step 18.
    2. NO:  It can be assumed that this malfunction is intermittent (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).
  18. STEP 18. Using scan tool MB991958, read the diagnostic trouble code. 
    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 (MUT-III). ).
      Fig 27: Connecting Scan Tool MB991958 To Data Link Connector
      G00809746Courtesy 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.
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Disconnect scan tool MB991958.

    Q: Is DTC 15 set? 

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