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Home >> Honda >> 2003 >> Civic Si >> Repair and Diagnosis >> Engine Performance >> System >> PGM-FI System (Hatchback) >> DTC Troubleshooting >> DTC P1121: TP Sensor Signal Lower Than Expected

DTC P1121: TP Sensor Signal Lower Than Expected

  1. Turn the ignition switch ON (II).
  2. Check the throttle position with the HDS or a scan tool.

    Is 12.9%, 0.6 V, or higher indicated when the throttle is fully opened? 

    YES:  Intermittent failure, system is OK at this time.

    NO:  Replace the throttle body (the TP sensor is not available separately) (see THROTTLE BODY REMOVAL/INSTALLATION ).