Throttle/Pedal Position Sensor D/F Voltage Correlation
Code P2139 indicates a voltage correlation fault between the throttle position sensor D and F circuits, or between the pedal position sensor D and F circuits, depending on the vehicle. These sensors are typically redundant potentiometers within the accelerator pedal position (APP) sensor or throttle position sensor (TPS). The PCM detects that the voltage signals from sensor D and sensor F do not match within a specified range, suggesting a wiring issue, poor connection, or sensor failure.
1. Most Common Causes
- Faulty accelerator pedal position sensor
- Faulty throttle position sensor
- Open or shorted wiring in sensor circuits
- Poor electrical connections or corroded terminals
- Failed PCM (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or limp mode
- Poor acceleration or hesitation
- Erratic throttle response
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and record freeze frame data.
Step 2: Visually inspect wiring and connectors for damage, corrosion, or loose pins.
Step 3: Using a multimeter, check voltage and ground at the sensor connectors per manufacturer specs.
Step 4: Compare sensor D and F voltage signals while slowly pressing the accelerator pedal; they should track smoothly.
Step 5: If signals are out of range or erratic, replace the faulty sensor (APP or TPS).
4. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The vehicle may enter limp mode, reducing power and increasing the risk of accidents. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and sensor replacement, depending on labor rates and parts prices.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.