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Home >> Honda >> 2004 >> Element DX, 2.4 YH2, Standard >> Repair and Diagnosis >> Engine Performance >> System >> PGM-FI System >> DTC Troubleshooting >> DTC P1121: TP Sensor Signal Lower Than Expected
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DTC P1121: TP Sensor Signal Lower Than Expected

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Open the throttle fully.
  4. Check the TP SENSOR in the DATA LIST with the HDS.

    Does the throttle position show less than 4.0° (REL) (14% (REL)) for 5 seconds? 

    1. YES-  Go to step  8.
    2. NO-  Go to step  5.
  5. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  6. Test-drive under these conditions:
    • ECT SENSOR above 15°F (70°C)
    • Engine speed at 1,400 RPM or more
    • Maintain a vehicle speed of 15 mph (24 km/h) or more for at least 2 seconds, then accelerate slowly.
  7. Monitor the OBD STATUS for DTC P1121 in the DTCs MENU with the HDS.

    Does the screen indicate FAILED? 

    1. YES-  Go to step  8.
    2. NO-  If the screen indicates PASSED, intermittent failure, system is OK at this time. If the screen indicates NOT COMPLETED, go to step  5 and recheck.
  8. Turn the ignition switch OFF.
  9. Replace the throttle body (the TP sensor is not available separately) (see THROTTLE BODY REMOVAL/INSTALLATION ).
  10. Turn the ignition switch ON (II).
  11. Reset the ECM/PCM with the HDS.
  12. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  13. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  14. Test-drive the vehicle at 16 mph (25 km/h) or more, and at 1,400 RPM or more. Maintain a vehicle speed at least 2 seconds, then accelerate slowly.
  15. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES-  If DTC P1121 is indicated, check for poor connections or loose terminals at the TP sensor and the ECM/PCM, then go to step  1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting .
    2. NO-  Go to step  16.
  16. Monitor the OBD STATUS for DTC P1121 in the DTCs MENU with the HDS.

    Does the screen indicate PASSED? 

    1. YES-  Troubleshooting is complete.
    2. NO-  If the screen indicates FAILED, check for poor connections or loose terminals at the TP sensor and the ECM/PCM, then go to step  1. If the screen indicates NOT COMPLETED, go to step  13 and recheck.
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