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Home >> Toyota >> 2003 >> Highlander Base, 2.4 D, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self Diagnostics - 4-Cylinder >> Diagnostic Tests >> DTC P0121: Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance Problem >> Diagnosis & Repair
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Diagnosis & Repair

NOTE:
  • Read freeze frame data using hand-held tester or OBD II scan tool, as freeze frame data records engine conditions when a malfunction is detected. When trouble shooting, this is useful for determining whether vehicle was running or stopped, engine was warmed up or not, air-fuel ratio was lean or rich, etc. at time of malfunction.
  • If any other codes besides DTC P0121 are output, trouble shoot those DTCs first.

Check if any other DTC besides DTC P0121 is output. If only DTC P0121 is output, replace throttle position sensor. See REMOVAL & INSTALLATION - 4-CYLINDER article. If DTC P0121 and other codes are output, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS  under SELF-DIAGNOSTIC SYSTEM.

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