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Home >> Hyundai >> 2003 >> Santa Fe Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.4L >> Diagnostic Tests >> DTC P0121: Throttle Position Sensor Circuit Range/Performance Problem >> Inspection/Repair >> Component Inspection
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Component Inspection

  1. Check TPS Performance Test.
    1. Ignition "ON" & Engine "ON".
    2. Install Scantool and select the "TP SENSOR" parameter on the CURRENT DATA.
    3. Monitor signal waveform of the "TP SENSOR" on the Scantool.

      Specification: TPS value changes smoothly in proportion with the MAFS.

      Fig 1: Monitor Signal Waveform Of TP Sensor On Scantool
      G07823249
    4. Is the TPS value within specification?

      YES

      • Check TPS for contamination, deterioration, or damage. Clean TPS with suitable cleaner as necessary and let air dry before reinstalling. If problem still exists, test with a new TP sensor and check for proper operation. If problem is corrected, replace TPS sensor and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

      NO

      • Go to " 2 Check TPS resistance" as below.
  2. Check TPS resistance.
    1. Ignition "OFF" & Engine "OFF".
    2. Disconnect TPS connector.
    3. Measure resistance between terminals 1 and 2 of the TPS connector (to TP sensor side).

      Specification: Approx. 3.5~6.5Ω (with throttle valve fully closed) at 20°C (68°F)

      Fig 2: Measuring Resistance Between Terminals 1 And 2 Of TPS Connector
      G07823250
    4. With still TPS connector disconnected, measure resistance between terminals 1 and 3 of the sensor connector (To sensor side).
    5. Operate the throttle valve slowly from the idle position to the full open position and check the resistance changes smoothly in proportion with the throttle valve opening angle.

      Specification: Resistance changes smoothly in proportion with the throttle valve opening angle.

      Fig 3: Measuring Resistance Between Terminals 1 And 3 Of Sensor Connector
      G07823251
    6. Is the measured resistance within specification?

      YES

      • Go to " 3 Check PCM" as below.

      NO

      • Substitute with a known - good TPS and check for proper operation. If the problem is corrected, replace TPS and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  3. Check PCM.
    1. Ignition "OFF" & Ignition "ON".
    2. Connect Scantool and Ignition "ON".
    3. Select simulation function on scantool.
    4. Simulate voltage at terminal 3 of TP sensor signal connector.
      Fig 4: Simulating Voltage At Terminal 3 Of TP Sensor Signal Connector
      G07823252
    5. Is TP sensor signal value changed according to simulation voltage?

      YES

      • Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

      NO

      • Substitute with a known - good PCM and check for proper operation.

        If the problem is corrected, replace PCM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

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