P2138 Code - Accelerator Pedal Position Sensor 1-2 Correlation
Quick Answer
The Accelerator Pedal Assembly contains 2 Accelerator Pedal Position (APP) sensors. Common causes include Faulty Accelerator Pedal Position Sensor, Accelerator Pedal Position Sensor harness is open or shorted, Accelerator Pedal Position Sensor circuit poor electrical connection. 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
- P2138 indicates Accelerator Pedal Position Sensor 1-2 Correlation.
- Common causes
- Common causes include Faulty Accelerator Pedal Position Sensor, Accelerator Pedal Position Sensor harness is open or shorted, Accelerator Pedal Position Sensor circuit poor electrical connection.
- 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.
Code P2138 Description
Both the APP sensors 1 and 2 signal percentages increase as the pedal is depressed, from approximately 0 percent at rest to above 95 percent when fully depressed.
The Diagnostic Trouble Code (DTC) will be set when the ECM detects that APP sensor 1 and APP sensor 2 disagree greater than 10 percent for less than 1 s or the ECM detects that both APP sensor 1 and APP sensor 2 are 5 percent greater than the learned minimum position for less than 1 s.
What are the Possible Causes of the DTC P2138?
- Faulty Accelerator Pedal Position Sensor
- Accelerator Pedal Position Sensor harness is open or shorted
- Accelerator Pedal Position Sensor circuit poor electrical connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P2138?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P2138 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P2138 Acura — Accelerator Pedal Position Sensor A/B Incorrect Voltage Correlation
- P2138 Buick — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Cadillac — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Chevrolet — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Dodge — Accelerator Pedal Position Sensor Circuit Range/Performance
- P2138 Ford — Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 GMC — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Honda — Accelerator Pedal Position Sensor A/B Incorrect Voltage Correlation
- P2138 Hyundai — Accelerator Pedal Position Sensor Circuit Range/Performance
- P2138 Infiniti — Accelerator Pedal Position Sensor Circuit Range/Performance
- P2138 Lexus — Throttle Pedal Position Sensor/Switch 'D' / 'E' Voltage Correlation
- P2138 Lincoln — Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 Mercedes-Benz — Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 Mercury — Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 Nissan — Accelerator Pedal Position Sensor Circuit Range/Performance
- P2138 Pontiac — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Saab — Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 Saturn — Accelerator Pedal Position Sensor 1-2 Correlation
- P2138 Scion — Throttle Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
- P2138 Toyota — Throttle Pedal Position Sensor/Switch 'D'/'E' Voltage Correlation
Frequently Asked Questions about P2138 Code
What does OBDII code P2138 mean?
Code P2138 indicates a mismatch or correlation issue between the two signals from the accelerator pedal position sensors, which are responsible for monitoring pedal movement.
What are the common symptoms of P2138?
Symptoms may include reduced engine power, poor throttle response, difficulty accelerating, the check engine light turning on, and the vehicle entering "limp mode."
What causes P2138 to occur?
The code can be triggered by a faulty accelerator pedal position sensor, damaged wiring or electrical connectors, or issues with the throttle body or related circuits.
Can I drive with code P2138?
Driving with P2138 is not recommended as it can lead to reduced engine performance and safety concerns due to unpredictable throttle response.
How can P2138 be diagnosed?
P2138 can be diagnosed using an OBDII scanner to confirm the code, inspecting the wiring, connectors, and sensors for damage, and testing the voltage output of the accelerator pedal position sensor.
How do I fix code P2138?
Common fixes include replacing the accelerator pedal position sensor, repairing damaged wiring or connectors, and ensuring proper communication between the sensor and the throttle body.
How much does it cost to repair P2138?
The repair cost varies but typically ranges from $100 to $300 for parts and labor, depending on whether the accelerator pedal assembly or wiring needs replacement.
Can cleaning the throttle body fix P2138?
Cleaning the throttle body may help if the issue is related to throttle body contamination, but this is not a guaranteed fix for P2138, which is primarily a sensor or wiring issue.
Will disconnecting the battery clear P2138?
Disconnecting the battery may temporarily clear the code, but if the underlying issue isn’t resolved, the code will likely reappear.
Is P2138 a common issue?
Yes, P2138 is relatively common in vehicles with electronic throttle control systems, especially as sensors or wiring age and become prone to failure.
Discuss the causes and fixes for P2138 OBDII Code
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You have to start by inspecting the Accelerator Pedal Position Sensor, if the connector is OK then you may have to replaced the sensor itself.
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P2138 2001 volkswagon passat what parts are needed. Check engine light is on and epc light came on but went off when stopped driving
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You may have a problem with the throttle position sensor. What size of engine is in your Passat?
Here is the location of the sensor of the 2.8 lt engine: -
Hello, have a pssat 2001 model v5 (vr5) 2,3 bensin ,170 horse Power 4motion, today on the way back from worck EPC, ABS and ESP lamp com on...on the diagnose com up P2138 CODE...what the problem to by ??? somebody know ? :)
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I have a 2007 Nissan Sentra that has been displaying a P2138 coupled with randomly entering limp mode which requires the car to be cut off and restarted after a few minutes. I have replaced the accelerator pedal assemply and the throttle body but the problem still persists. What would be the next step?
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Unfortunately, at this point there is not an easy fix. If you have already replaced the pedal assembly, then finding the solution can get a bit complicated. The problem is that the Pedal Position Sensors share the same circuit with other components inside the ECM. Here is a list of the components in the same circuit:
- Accelerator pedal position sensor (APP sensor 1 and 2)
- Crankshaft position sensor (POS)
- Refrigerant pressure sensor
- EVAP control system pressure sensorSo the next step is to check the wires and sensor from those components to the ECM.
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