P2135Powertrain
Powertrain · SAE
Throttle/Pedal Position Sensor A/B Voltage Correlation
Meaning
The two redundant throttle (or pedal) position sensors report values that disagree with each other. Unable to determine the true position, the ECU activates a safety strategy.
Common causes
- Faulty throttle body or pedal sensor (one track out of calibration)
- Connector or wiring with intermittent contact on one of the two signals
- Corrosion or moisture in the connector
- Unstable shared ground or supply
- Internally worn dual sensor
Symptoms
- Reduced-power limp mode
- Poor or no throttle response
- Rough idle or stalling
- Acceleration that stops at a certain load
- Check-engine light on
Severity
Moderate: the ECU limits power for safety; driving is still possible but heavily restricted.
What to do
- Read both signals live and compare their behaviour across the full travel
- Check the shared supply and ground feeding the two sensors
- Inspect the connector for corrosion, moisture or loose pins
- Replace the throttle body or pedal sensor if one track is out of calibration