P2128 2018 GMC Sierra Code - Accelerator Pedal Position Sensor 2 Circuit High Voltage
Quick Answer
The diagnostic trouble code P2128 in a 2018 GMC Sierra indicates an issue with the Accelerator Pedal Position Sensor 2 Circuit registering high voltage. Common causes include Faulty Accelerator Pedal Position Sensor, Wiring issues such as shorts or open circuits, ECM malfunction. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P2128 2018 GMC Sierra indicates Accelerator Pedal Position Sensor 2 Circuit High Voltage.
- Common causes
- Common causes include Faulty Accelerator Pedal Position Sensor, Wiring issues such as shorts or open circuits, ECM malfunction.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P2128 2018 GMC Sierra Description
The diagnostic trouble code P2128 in a 2018 GMC Sierra indicates an issue with the Accelerator Pedal Position Sensor 2 Circuit registering high voltage. This sensor is responsible for monitoring the position of the accelerator pedal and sending this information to the engine control module (ECM). The ECM uses this data to determine the appropriate fuel delivery and ignition timing for optimal engine performance.
Common Causes of P2128 2018 GMC Sierra
- Faulty Accelerator Pedal Position Sensor
- Wiring issues such as shorts or open circuits
- ECM malfunction
- Corrosion or damage to sensor connectors
- Environmental factors such as moisture intrusion
Symptoms of P2128 2018 GMC Sierra
- Erratic throttle response
- Poor fuel efficiency
- Stalling or hesitation during acceleration
- Check Engine Light illuminated
- Reduced engine performance
How to Fix P2128 2018 GMC Sierra
- Begin by conducting a thorough diagnostic scan to confirm the P2128 code and identify the specific cause of the high voltage reading.
- Inspect the Accelerator Pedal Position Sensor and its wiring for any visible damage or corrosion. Replace the sensor if necessary.
- Check the wiring harness for any shorts or open circuits. Repair or replace damaged wiring as needed.
- Test the ECM to ensure it is functioning correctly and communicating with the sensor appropriately. Replace the ECM if faulty.
- Clear the trouble code from the ECM memory and perform a test drive to verify that the issue has been resolved.
Cost to Fix P2128 2018 GMC Sierra
The typical repair costs for addressing the Accelerator Pedal Position Sensor 2 Circuit High Voltage issue can range from $200 to $500, including parts and labor. However, it is essential to note that specific diagnosis time and labor rates at auto repair shops can vary significantly based on factors such as location, vehicle make and model, and engine type. Auto repair shops commonly charge between $80 and $150 per hour for labor, with rates potentially higher in metropolitan areas or at dealerships and lower at independent shops. It is advisable to obtain local estimates for a more accurate cost assessment.
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Frequently Asked Questions about P2128 2018 GMC Sierra Code
1. What does the OBDII code P2128 mean on a 2018 GMC Sierra?
P2128 indicates a high voltage issue in the Accelerator Pedal Position Sensor 2 (APP Sensor 2) circuit, which monitors the position of the accelerator pedal.
2. What are the symptoms of code P2128 in a 2018 GMC Sierra?
Symptoms may include reduced engine power, difficulty accelerating, the throttle not responding properly, and the illumination of the check engine light.
3. What causes the P2128 code on a 2018 GMC Sierra?
Common causes include a faulty accelerator pedal position sensor, damaged wiring or connectors in the APP Sensor 2 circuit, or a malfunctioning engine control module (ECM).
4. Can I drive my 2018 GMC Sierra with the P2128 code?
While the vehicle may still be drivable, it will likely experience reduced performance. Prolonged driving without repairs could lead to further damage.
5. How do I fix the P2128 code on my 2018 GMC Sierra?
Repairs may involve replacing the APP sensor, repairing damaged wiring or connectors, or reprogramming or replacing the ECM if necessary.
6. How do I diagnose the P2128 code on a 2018 GMC Sierra?
Diagnosis involves using a scan tool to check for related codes, inspecting the APP sensor and its wiring for damage, and testing the voltage and continuity of the circuit.
7. How much does it cost to fix a P2128 code on a 2018 GMC Sierra?
Repair costs vary depending on the issue but typically range from $150 to $400 for parts and labor, with the accelerator pedal sensor being the most common replacement.
8. Can a dirty or stuck accelerator pedal cause the P2128 code?
While less common, a dirty or sticky pedal could impact sensor readings and should be inspected if other causes are ruled out.
9. Will clearing the P2128 code fix the problem on a 2018 GMC Sierra?
Clearing the code will temporarily turn off the check engine light but won’t resolve the underlying issue causing the high voltage in the APP Sensor 2 circuit.
10. Is the P2128 code related to the throttle body in a 2018 GMC Sierra?
Indirectly, yes. A faulty APP sensor or wiring can affect throttle body operation since the ECM uses APP sensor data to control throttle response.
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