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DTC 12: TP Sensor System (Open Circuit): Diagnosis

Required Special Tool: 

  1. MB991502: Scan Tool (MUT-II)
  1. STEP 1. Using scan tool MB991502, check data list item 11: TP Sensor. 
    CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
    1. Connect scan tool MB991502 to the data link connector.
      Fig 1: Connecting Scan Tool To Data Link Connector
      G01876159Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991502 to the data reading mode for item 11, TP Sensor.
      • With the throttle valve in the idle position, voltage should measure between 335 and 935 mV.
      • With the throttle valve in the full-open position, voltage should measure between 4,400 and 5,300 mV.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 335 and 935 mV at idle, and between 4,400 and 5,300 mV in the full-open position? 

    1. YES:  It can be assumed that this malfunction is intermittent.
    2. NO:  Go to Step 2.
  2. STEP 2. Measure the TP sensor output voltage at the TP sensor connector B-03 by backprobing. 
    Fig 2: Measuring TP Sensor Output Voltage At TP Sensor Connector B-03
    G01876160Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    1. Do not disconnect connector B-03.
    2. Turn the ignition switch to the "ON" position.
    3. Measure the voltage between terminal 1 and ground by backprobing.
      • With the throttle valve in the idle position, voltage should measure between 0.335 and 0.935 volt.
      • With the throttle valve in the full-open position, the voltage should measure between 4.4 and 5.3 volts.
      Fig 3: Measuring Voltage Between Terminal 1 & Ground
      G01876161Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 0.335 and 0.935 volt at idle, and between 4.4 and 5.3 volts in the full-open position? 

    1. YES:  Go to Step 3.
    2. NO:  Go to  Step 8 .
  3. STEP 3. Measure the TP sensor output voltage at PCM connector C-116 by backprobing. 
    Fig 4: Measuring TP Sensor Output Voltage At PCM Connector C-116
    G01876162Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    1. Do not disconnect connector C-116.
    2. Turn the ignition switch to the "ON" position.
    3. Measure the voltage between terminal 78 and ground by backprobing.
      • With the throttle valve in the idle position, voltage should measure between 0.335 and 0.935 volt.
      • With the throttle valve in the full-open position, voltage should measure between 4.4 and 5.3 volts.
      Fig 5: Measuring Voltage Between Terminal 78 & Ground
      G01876163Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 0.335 and 0.935 volt at idle, and between 4.4 and 5.3 volts in the full-open position? 

    1. YES:  Go to Step 4.
    2. NO:  Go to  Step 6 .
  4. STEP 4. Check TP sensor connector B-03 and PCM connector C-116 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 6: Checking TP Sensor Connector B-03
    G01876164Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 7: Checking PCM Connector C-116
    G01876165Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connectors and terminals in good condition? 

    1. YES:  Go to Step 5.
    2. NO:  Repair or replace the damaged components.
  5. STEP 5. Using scan tool MB991502, check data list item 11: TP Sensor. 
    CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
    1. Connect scan tool MB991502 to the data link connector.
      Fig 8: Connecting Scan Tool To Data Link Connector
      G01876166Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Turn the ignition switch to the "ON" position.
    3. Set scan tool MB991502 to the data reading mode for item 11, TP Sensor.
      • With the throttle valve in the idle position, voltage should measure between 335 and 935 mV.
      • With the throttle valve in the full-open position, voltage should measure between 4,400 and 5,300 mV.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the sensor voltage between 335 and 935 mV at idle, and between 4,400 and 5,300 mV in the full-open position? 

    1. YES:  It can be assumed that this malfunction is intermittent.
    2. NO:  Replace the PCM.
  6. STEP 6. Check TP sensor connector B-03 and PCM connector C-116 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 9: Checking TP Sensor Connector B-03
    G01876167Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 10: Checking PCM Connector C-116
    G01876168Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connectors and terminals in good condition? 

    1. YES:  Go to Step 7.
    2. NO:  Repair or replace the damaged components.
  7. STEP 7. Check the harness for open circuit or damage between TP sensor connector B-03 terminal 1 and PCM connector C-116 terminal 78. 
    Fig 11: Checking TP Sensor Connector B-03 For Open Circuit Or Damage
    G01876169Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 12: Checking PCM Connector C-116 For Open Circuit Or Damage
    G01876170Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES:  Go to  Step 5 .
    2. NO:  Repair or replace the harness wire.
  8. STEP 8. Measure the power supply voltage from the PCM at the TP sensor connector B-03 by backprobing. 
    Fig 13: Measuring Power Supply Voltage From PCM At TP Sensor Connector B-03
    G01876171Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    1. Do not disconnect connector B-03.
    2. Turn the ignition switch to the "ON" position.
    3. Measure the voltage between terminal 3 and ground by backprobing.
      • The voltage should measure between 4.9 and 5.1 volts.
      Fig 14: Measuring Voltage Between Terminal 3 & Ground
      G01876172Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 4.9 and 5.1 volts? 

    1. YES:  Go to  Step 14 .
    2. NO:  Go to Step 9.
  9. STEP 9. Measure the power supply voltage at PCM connector C-118 by backprobing. 
    Fig 15: Measuring Power Supply Voltage At PCM Connector C-118
    G01876173Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    1. Do not disconnect connector C-118.
    2. Turn the ignition switch to the "ON" position.
    3. Measure the voltage between terminal 46 and ground by backprobing.
      • The voltage should measure between 4.9 and 5.1 volts.
      Fig 16: Measuring Voltage Between Terminal 46 & Ground
      G01876174Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the measured voltage between 4.9 and 5.1 volts? 

    1. YES:  Go to Step 10.
    2. NO:  Go to  Step 12 .
  10. STEP 10. Check TP sensor connector B-03 and PCM connector C-118 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 17: Checking TP Sensor Connector B-03
    G01876175Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 18: Checking PCM Connector C-118
    G01876176Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connectors and terminals in good condition? 

    1. YES:  Go to Step 11.
    2. NO:  Repair or replace the defective components.
  11. STEP 11. Check the harness for open circuit or damage between TP sensor connector B-03 terminal 3 and PCM connector C-118 terminal 46. 
    Fig 19: Checking TP Sensor Connector B-03 For Open Circuit Or Damage
    G01876177Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 20: Checking PCM Connector C-118 For Open Circuit Or Damage
    G01876178Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES:  Go to  Step 5 .
    2. NO:  Repair or replace the harness wire.
  12. STEP 12. Check TP sensor connector B-03 and PCM connector C-118 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 21: Checking TP Sensor Connector B-03
    G01876179Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 22: Checking PCM Connector C-118
    G01876180Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connectors and terminals in good condition? 

    1. YES:  Go to Step 13.
    2. NO:  Repair or replace the damaged components.
  13. STEP 13. Check the harness for a short circuit to ground between TP sensor connector B-03 terminal 3 and PCM connector C-118 terminal 46. 
    Fig 23: Checking TP Sensor Connector B-03 For Short Circuit To Ground
    G01876181Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 24: Checking PCM Connector C-118 For Short Circuit To Ground
    G01876182Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES:  Go to  Step 5 .
    2. NO:  Repair or replace the harness wire.
  14. STEP 14. Check TP sensor connector B-03 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 25: Checking TP Sensor Connector B-03
    G01876183Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connector and terminals in good condition? 

    1. YES:  Go to Step 15.
    2. NO:  Repair or replace the damaged components.
  15. STEP 15. Check the TP sensor. 
    1. Disconnect connector B-03 and measure at the TP sensor side.
      Fig 26: Disconnecting Connector B-03 & Measuring TP Sensor Side
      G01876184Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance between the TP sensor connector terminals 2 and 3.
      1. Specified resistance: 2.0 - 4.0 kohm 
      Fig 27: Measuring Resistance Between TP Sensor Connector Terminals 2 & 3
      G01876185Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Measure the resistance between the TP sensor connector terminals 1 and 2.
      Fig 28: Measuring Resistance Between TP Sensor Connector Terminals 1 & 2
      G01876186Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Move the throttle valve from the idle position to the full-open position.
      • The resistance should change smoothly in proportion to the opening angle of the throttle valve.

    Q: Does the resistance change smoothly between 2.0 - 4.0 kohm in proportion to the opening angle of the throttle valve? 

    1. YES:  Go to Step 16.
    2. NO:  Replace the TP sensor.
  16. STEP 16. Check PCM connectors C-116 and C-118 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
    Fig 29: Checking PCM Connectors C-116 & C-118
    G01876187Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Are the connectors and terminals in good condition? 

    1. YES:  Go to Step 17.
    2. NO:  Repair or replace the damaged components.
  17. STEP 17. Check the harness for a short circuit to ground or damage between TP sensor connector B-03 terminal 1 and PCM connector C-116 terminal 78. 
    Fig 30: Checking TP Sensor Connector B-03 For Short Circuit To Ground Or Damage
    G01876188Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 31: Checking PCM Connector C-116 For Circuit To Ground Or Damage
    G01876189Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the harness wire in good condition? 

    1. YES:  Go to Step 18.
    2. NO:  Repair or replace the harness wire.
  18. STEP 18. Check the TP sensor connector and harness for a short circuit to ground between the TP sensor and the auto-cruise control-ECU connector. 

    Q: Are the connector and harness wire in good condition? 

    1. YES:  Adjust the TP sensor.
    2. NO:  Repair or replace the damaged components.
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