LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mitsubishi >> 1995 >> Pickup Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Tests W/Codes - OBD-II (2.4L) >> Diagnostic Tests >> Code P0120: Throttle Position (TP) Sensor Circuit Failure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Code P0120: Throttle Position (TP) Sensor Circuit Failure

NOTE: For component terminal identification, see TERMINAL IDENTIFICATION  in this article. For wiring diagrams, see WIRING DIAGRAMS in the WIRING DIAGRAMS  section.
  1. If using scan tool, go to step 3). Disconnect TP sensor connector. Using DVOM, check resistance between TP sensor terminals No. 1 and No. 4. If resistance is not 3500-6500 ohms, replace TP sensor. If resistance is as specified, go to next step.
  2. Check resistance between TP sensor terminals No. 3 and No. 4. While monitoring DVOM, slowly open throttle from idle to fully open position. If resistance does not change smoothly, replace TP sensor. If resistance changes smoothly, go to step 4).
  3. Turn ignition switch to ON position. Using scan tool, read TP sensor voltage value. With throttle at idle, value should read 6-20 percent. Value should increase while slowly opening throttle. At wide open throttle, value should read 100 percent. If value is not as specified, replace TP sensor. If value is as specified, go to next step.
  4. Disconnect TP sensor connector. Using DVOM, check continuity between chassis ground and specified TP sensor connector terminal. See TP SENSOR CONNECTOR GROUND CIRCUIT IDENTIFICATION  table. If continuity does not exist, repair wiring harness as necessary. If continuity exists, go to next step.
    TP SENSOR CONNECTOR GROUND CIRCUIT IDENTIFICATION

    Application Terminal No.
    Expo & Summit Wagon 1
  5. Disconnect TP sensor connector and PCM connector. Ground specified PCM connector terminal. See TP SENSOR-TO-PCM WIRING HARNESS TERMINAL IDENTIFICATION  table. Check for continuity between chassis ground and specified TP sensor connector terminal. See TP SENSOR-TO-PCM WIRING HARNESS TERMINAL IDENTIFICATION  table. If continuity does not exist, repair wiring harness as necessary. If continuity exists, go to next step.
    TP SENSOR-TO-PCM WIRING HARNESS TERMINAL IDENTIFICATION

    Application TP Sensor Terminal No. PCM Terminal No.
    Expo & Summit Wagon 3 64
    4 61
  6. Check voltage between chassis ground and specified TP sensor connector terminal. See TP SENSOR VOLTAGE CIRCUIT IDENTIFICATION  table. If voltage is not 4.8-5.2 volts, replace PCM. If voltage is as specified, condition required to set trouble code is not present at this time. Go to next step.
    TP SENSOR VOLTAGE CIRCUIT IDENTIFICATION

    Application TP Sensor Terminal No.
    Expo & Summit Wagon 4
  7. Test is complete. Intermittent problem may exist. Road test vehicle (if necessary) and attempt to duplicate conditions that caused original complaint. Recheck for codes. If no codes are displayed, go to INTERMITTENT FAULTS .
scientia non olet · About LEMON Manuals