L
p0121
Moderate
Lexus · SUVs
Throttle/Pedal Position Sensor/Switch B Range/Performance
Quick Answer
Error code P0121 on your Lexus SUVs means: Throttle/Pedal Position Sensor/Switch B Range/Performance. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Faulty accelerator pedal sensor
  2. Throttle position sensor malfunction
  3. Throttle body contamination
  4. Electrical connector corrosion
  5. Wiring harness damage
How to Fix It
1
Inspect accelerator pedal sensor connectors
2
Test pedal sensor resistance through full range
3
Clean throttle body with appropriate cleaner
4
Check wiring for continuity and resistance
5
Perform accelerator pedal calibration
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
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