P2128 Fault Code

Throttle/Pedal Position Sensor/Switch E Circuit High

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2128 fault code is triggered when the throttle/pedal position sensor or switch E circuit is detected to be operating at a high voltage than expected. This code can indicate issues with the sensor itself or the circuit it is connected to. The throttle position sensor is crucial for managing air intake and engine performance. If it malfunctions, it may lead to reduced engine power and performance issues.

What are the symptoms of the P2128 code?

Symptoms of a P2128 code may consist of:

• Check Engine Light (CEL) illuminated on the dashboard.
• Reduced engine performance or power loss.
• Unresponsive or erratic throttle behavior.
• Difficulty in accelerating or maintaining speed.
• In some cases, the vehicle may enter limp mode to protect the engine.

What causes the P2128 code?

Common causes for the P2128 fault code include:

• A faulty throttle position sensor (TPS).
• Damaged wiring or connectors leading to the TPS.
• Short circuits or open circuits in the throttle position sensor circuit.
• Issues with the engine control module (ECM) or malfunctioning software.
• Malfunctions in the pedal position sensor circuit.

How to fix P2128?

To resolve the P2128 fault code, follow these steps:

1. Use an OBD-II scanner to verify the code and check for additional codes.
2. Inspect the throttle position sensor for physical damage and ensure it is securely connected.
3. Check for damaged wiring or connectors in the circuit related to the throttle position sensor.
4. Test the throttle position sensor using a multimeter to ensure it operates within manufacturer specifications.
5. If necessary, replace the throttle position sensor.
6. Clear the fault codes from the ECM and conduct a test drive to see if the code returns.
7. If the issue persists, consider having the engine control module diagnosed for software issues.