P1121high severityPowertrain
Accelerator Pedal Position Sensor Range/Performance
on 2009 Toyota Matrix 2.4L I4 · FWD
What this code means
The APP sensor signal is outside expected range or not performing correctly.
Symptoms
- CEL
- Erratic throttle
- Surging
- Reduced power
Common causes
- Faulty APP sensor
- Intermittent connection
- Floor mat interference
- Faulty ECM
Diagnostic steps
- Monitor APP sensor live data
- Wiggle test connector
- Check pedal travel
- Test voltage range
Repair notes
Replace APP sensor.
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