By Ezra Lane The P2138 Nissan code indicates a voltage correlation fault in throttle/pedal position sensors 'D' and 'E'. This issue can lead to significant drivability concerns, such as poor acceleration, rough idling, and a potential limp mode activation, which limits speed for safety. Common causes include damaged wiring, corrosion on sensor terminals, or mechanical faults in the accelerator pedal. Diagnostic procedures require an OBD-II scanner, multimeter, and visual inspection tools. Repair costs vary, typically ranging between $100 and $300, and it is crucial to address this code quickly to ensure safe vehicle operation. More detailed insights await.
P2138 Nissan Code Meaning
The P2138 code indicates a voltage correlation problem in the accelerator pedal position sensor circuit, affecting throttle position sensors 'D' and 'E'.
It can cause drivability issues like reduced performance.
Diagnosis involves checking the sensor and wiring; repairs may include sensor replacement or fixing wiring problems.
Error Code P2138 Symptoms
Symptoms of the P2138 error code can affect how your vehicle runs and how you feel while driving. When the throttle or pedal position sensor is not working right, it can cause several problems that make driving difficult.
If you have the P2138 code, you might notice these signs:
- Poor Acceleration: Your car may not speed up well when you press the gas pedal. This can make driving frustrating.
- Hesitation or Stalling: You may feel the car hesitate or even stall when you try to speed up, especially on highways. This can be dangerous.
- Rough Idling: When you stop at lights or drive slowly, the engine might shake or run unevenly. This suggests you need to check the accelerator position sensor.
You may also notice that your fuel efficiency drops. The engine might not mix air and fuel properly because of the sensor issues.
If the accelerator pedal doesn't respond as it should, you might feel stuck. Fixing these problems quickly helps keep your vehicle performing well and ensures safety on the road.
Causes of Nissan P2138 Fault Code
Understanding the P2138 fault code can help you maintain your vehicle better. This code usually appears when the accelerator pedal position sensor isn't working right. When this sensor doesn't send the right signals to the Engine Control Module (ECM), it can cause your vehicle to perform erratically and may pose safety risks.
Here are a few reasons why the P2138 code may show up:
- Damaged Wiring or Connectors: If the wiring is broken or corroded, it can interrupt the electrical signals and trigger the P2138 code.
- Corrosion on Sensor Terminals: Dirt or rust at the sensor connection points can mess with the signals, making it hard for the ECM to get the right information.
- Mechanical Issues: If the accelerator pedal is stuck or not moving freely, it can lead to incorrect performance readings. This can also cause the ECM to set off the fault code.
Sometimes, the ECM itself can have software or hardware problems that lead to wrong signal readings from the accelerator pedal position sensor. Fixing these issues quickly can help keep your vehicle running smoothly.
Tools Needed to Diagnose
To diagnose the P2138 fault code, you need some important tools to check the vehicle's accelerator pedal position sensor and its parts. Here are the tools you should have:
- OBDII Scanner: This tool helps you read the P2138 code and any other codes stored in the car's computer. It helps you find the problem and understand how the sensors are working.
- Multimeter: You can use a multimeter to test the voltage and resistance of the accelerator pedal position sensor. This tool checks if the readings match what the manufacturer expects, helping you determine if the sensor is working properly.
- Wiring Diagram Tools: These tools show you the wiring for the accelerator pedal position sensor. They help you locate any short circuits or damage in the wires, making it easier to inspect everything.
You will also need basic hand tools, like screwdrivers and sockets, to look at, fix, or change parts related to the accelerator pedal position sensor.
Having these tools ready will help you diagnose the P2138 fault code effectively.
How to Fix P2138 Nissan Error Code – Step by Step
Step 1: Use an OBDII scanner to confirm the presence of the P2138 error code.
Check for any additional trouble codes that may indicate related issues.
Step 2: Conduct a visual inspection of the accelerator pedal position sensor and its wiring harness.
Look for any signs of damage, corrosion, or loose connections that may disrupt signal transmission.
Step 3: Test the resistance and voltage output of the accelerator pedal position sensor against the manufacturer's specifications.
This is crucial for identifying any discrepancies that could indicate a faulty sensor.
Step 4: If the sensor fails to meet specifications, proceed to replace it with a new one.
Ensure that it is installed correctly.
Step 5: Reconnect all wiring and connectors to maintain system integrity, ensuring everything is secure and functional.
Common Diagnosis Mistakes
Overlooking key details when diagnosing the P2138 code can lead to mistakes and unnecessary repairs. A good diagnosis looks at many factors that affect how the sensors work.
Common mistakes during P2138 diagnostics include:
- Neglecting Wiring and Connectors: Technicians might not check the condition of wiring and connectors. If these are damaged or corroded, it can lead to wrong conclusions about how well the sensor is working.
- Inadequate Sensor Verification: Not checking both the accelerator pedal position sensor and throttle position sensor together can lead to replacing parts that don't need to be changed. It's important to evaluate both sensors to get the right diagnosis.
- Ignoring Environmental Factors: Technicians may forget to consider how the environment affects the sensors. Things like moisture or dirt buildup can impact how the sensors perform and cause false codes.
Also, not checking for software updates or recalibrations in the Engine Control Module (ECM) can lead to wrong diagnoses.
A careful inspection, including checking the accelerator pedal assembly, is necessary to avoid costly errors. Each of these points is important for accurately diagnosing the P2138 code.
P2138 Nissan Repair Cost
Repairing the P2138 code can cost different amounts based on various factors. The main cost comes from fixing or replacing the accelerator pedal position sensor, which usually costs between $100 and $300.
In addition to this, you might have to pay for diagnostics. These fees depend on how the mechanic checks the vehicle.
Labor costs can also vary a lot. They typically range from $80 to $150 per hour, depending on where you live and how complicated the repair is.
If there are other issues, like wiring problems or issues with the Engine Control Module (ECM), your repair costs could go up. This would mean needing extra parts and more time to fix everything.
To get a precise estimate, it's best to talk to a qualified mechanic. They can give you a price that fits your vehicle's condition and local prices.
Knowing these costs can help you prepare for the expenses related to the P2138 Nissan code.
Related Error Codes on Nissan
When dealing with the P2138 code in Nissan cars, it's important to look at other related error codes. These codes usually point to problems with the accelerator pedal position sensor or the throttle position sensor, which can make repairs harder and impact how the car runs.
Here are some common error codes that often show up with the P2138 code:
| Error Code | Description | Potential Impact |
|---|---|---|
| P2127 | Accelerator Pedal Position Sensor Circuit Low | Reduced throttle response, limp mode |
| P2128 | Accelerator Pedal Position Sensor Circuit High | Erratic acceleration, stalling |
| P2129 | Accelerator Pedal Position Sensor Range/Performance Problem | Inconsistent vehicle performance |
| P2106 | Throttle Actuator Control System Range/Performance Problem | Engine power loss, unsafe driving conditions |
| P2119 | Throttle Actuator Position Performance Problem | Erratic engine behavior, stalling |
Ignoring these related codes while fixing the P2138 code can lead to more problems later on. A thorough check is needed to find any wiring issues or problems with the engine control module (ECM) software that might be causing these important systems to fail.
Can I drive safely with P2138 Nissan?
Driving a Nissan with a P2138 code can be dangerous. This code means the gas pedal and throttle aren't working well together.
You might have trouble speeding up or the car might stall. It's best to get it fixed before driving far or in busy areas.
People Also Ask
What Vehicles Are Commonly Affected by the P2138 Code?
The P2138 code usually affects many Nissan cars, like the Altima, Maxima, Sentra, Rogue, and Frontier. These cars were made between 2002 and 2020. They often have problems with their electronic throttle control systems.
Can P2138 Affect Fuel Economy?
Yes, the P2138 code can hurt your fuel economy. If the accelerator pedal sensor doesn't work right, the engine can't mix air and fuel properly. This can make your car use more gas and go fewer miles on each gallon.
Is P2138 More Common in Older Nissan Models?
Yes, older Nissan models often have the P2138 code more often. This is because their parts can wear out over time, have more electrical problems, and can get rusty. It's important to check and take care of these cars regularly to avoid issues.
How Can I Prevent P2138 From Occurring Again?
To stop the P2138 problem from happening again, check the throttle position sensor and its wires often. Keep electrical connections clean, drive carefully, and fix any engine problems quickly during regular car checks. This will help keep your car running well!
Are There Any Recalls Related to the P2138 Code?
Yes, Nissan has had recalls for problems with the accelerator pedal position sensor. If you own a Nissan, check the National Highway Traffic Safety Administration (NHTSA) website or contact Nissan to see if your car is affected by any recalls.