P0124Powertrain
Powertrain · SAE
TPS/Accelerator Pedal Sensor A — Intermittent Signal
Meaning
The track A signal of the throttle position or accelerator pedal position sensor shows erratic fluctuations unrelated to pedal movement. The ECU detects non-continuous plausibility violations.
Common causes
- Loose TPS/APP connector or intermittent contacts
- Chafed wiring with micro-breaks on the signal A circuit
- Worn resistive element in the TPS/APP sensor
- Intermittent sensor ground connection
- Interference on the signal circuit
Symptoms
- Intermittently illuminated check-engine light
- Sudden jerks or irregularities during acceleration
- Possible intermittent activation of limp-home mode
- Fault code that self-clears but returns
- Anomalous behavior only in certain cable positions or temperatures
Severity
Moderate: intermittent fault can cause sudden power limitation events; difficult to reproduce in the workshop.
What to do
- Inspect the TPS/APP connector: verify contacts and locking
- Wiggle the wiring gently while monitoring the signal on a scan tool to locate intermittent contacts
- Check sensor resistance with the pedal in various positions
- Verify the sensor ground connection
- Replace the sensor or repair the wiring once the fault location is found