The P2138 code is a diagnostic trouble code (DTC) that pertains to an issue with the throttle and pedal position sensors in your vehicle. These sensors are crucial components that communicate the driver’s acceleration intentions to the engine control module (PCM).
What Does the P2138 Code Mean?
OBD-II Code P2138 is defined as a Throttle/Pedal Position Sensor/Switch “D”/”E” Voltage Correlation. This code indicates that there is a discrepancy in the voltage readings between the throttle position sensor and the pedal position sensor, which could lead to improper engine performance.
What Causes the P2138 Code?
The P2138 code can be triggered by several issues, including:
- Accelerator Pedal Position (APP) assembly failure
- Throttle Position Sensor (TPS) failure
- Powertrain Control Module (PCM) failure
- Wiring issues or poor connections
What Are the Symptoms of the P2138 Code?
Drivers experiencing the P2138 code may notice the following symptoms:
- Decreased engine performance
- Engine may enter limp home mode, which limits speed and performance
How Serious Is the P2138 Code?
The P2138 code is classified as urgent. It indicates a significant malfunction that could lead to severe engine damage or safety risks for the driver and passengers. Immediate action is recommended to prevent further complications.
How to Diagnose the P2138 Code
To diagnose the P2138 code effectively, a mechanic should follow these steps:
- Use an OBD-II scanner to confirm the P2138 code and check for any accompanying codes.
- Inspect the wiring and connectors for the throttle and pedal position sensors for damage or corrosion.
- Test the voltage output of the throttle position sensor and pedal position sensor.
- Check the functionality of the APP and TPS assemblies.
- Evaluate the PCM for any faults.
Common Repairs for the P2138 Code
Common repairs for the P2138 code include:
- Replacing the Accelerator Pedal Position (APP) assembly
- Replacing the Throttle Position Sensor (TPS)
- Repairing or replacing damaged wiring and connectors
- Replacing the Powertrain Control Module (PCM) if necessary
How Much Does It Cost to Fix the P2138 Code?
The cost to fix the P2138 code can vary widely based on the underlying issue. Potential costs may range from $100 to $1,500, depending on whether a sensor needs replacing or a more complex repair involving the PCM is required.
Can I Fix the P2138 Code Myself?
While some skilled DIY enthusiasts may be able to diagnose and fix the P2138 code by following the diagnostic steps and repairing wiring or replacing sensors, this code often indicates a problem that may require professional expertise. It is recommended to consult a qualified mechanic if you are unsure or if the issue persists after your efforts.
