What does the fault code P2138 mean in Dongfeng Nissan vehicles?

[Bethany]

Dongfeng Nissan vehicle fault code P2138 indicates a malfunction in the throttle or accelerator pedal sensor. The solution is to have the fault repaired at a repair shop or 4S store, and then clear the fault code. Throttle failure: When the throttle fails, the vehicle may exhibit symptoms such as engine shaking, unstable idle speed, weak acceleration, and difficulty starting when cold. In this case, the throttle needs to be cleaned again, especially the oil sludge attached to the throttle, which must be thoroughly removed. Accelerator pedal sensor failure: When the accelerator pedal fails, the vehicle may show problems such as weak acceleration, severe jerking, and failure to move when accelerating. In this situation, the accelerator pedal sensor should be inspected, and it is also important to use high-quality fuel daily. Dongfeng Nissan Passenger Vehicle Company was established in June 2003 and is an important passenger vehicle division under Dongfeng Motor Co., Ltd. It is engaged in the research and development, procurement, manufacturing, sales, and service of NISSAN brand passenger vehicles, making it one of the domestic automotive enterprises with a complete value chain.

[DelRhett]

The P2138 trouble code in Dongfeng Nissan is something I frequently encounter in the repair shop. Simply put, it means the signals from the accelerator pedal and throttle position sensor don't match. Last time, a Qashqai had this issue, with the owner complaining about sluggish response when pressing the accelerator. We first checked the voltage signals from both sensors of the accelerator pedal and found abnormal fluctuations using a multimeter. Then we inspected the wiring for any damage or loose connections, especially the harness in the engine compartment which is prone to aging. Finally, we discovered that oxidation on the throttle position sensor connector caused poor contact. I recommend not driving the vehicle forcefully as signal desynchronization can affect acceleration safety. It's best to use professional equipment to read the data stream and pinpoint the fault as soon as possible.

[LaHailey]

My Tiida also had the P2138 trouble light come on last year, and I initially thought it was a minor issue. This fault code specifically indicates an abnormal correlation in signal voltage between the throttle position sensor and the throttle body sensor. In simple terms, the ECU detects a mismatch between your throttle pedal input and the throttle opening angle. There are three common causes: the pedal sensor itself failing, loose wiring connections (especially the harness near the driver's footwell), or carbon buildup causing throttle body sticking. I first checked the real-time data stream with an OBD scanner to confirm it was a sensor issue. The repair cost over 300 yuan to replace the pedal sensor, and the trouble light disappeared after recalibration. A reminder to everyone: regularly cleaning dust under the floor mats can prevent poor wiring contact.

[Emersyn]

Don't panic when encountering P2138 trouble code, focus on checking three key areas. First is the dual sensors in the accelerator pedal assembly, which tend to fail after 5-7 years of use - replace if resistance exceeds 1 kiloohm. Second, inspect wiring harness connectors, especially the gray plug near the firewall for oxidation or looseness. Lastly, check the throttle position sensor as carbon buildup can cause signal drift. Having handled similar issues in X-Trail vehicles, 80% of cases were sensor-related. Remember to perform throttle relearn using a scan tool after replacement. During routine maintenance, avoid spilling liquids near the accelerator pedal as moisture can cause short circuits in the electrical system.

[SanDante]

Last time I helped a friend deal with the P2138 fault in their Sunny car. This code specifically indicates a mismatch between the throttle pedal sensor and the throttle opening signal. Typical symptoms include the tachometer jumping during acceleration and the car lurching when the throttle is pressed suddenly. We first disconnected the negative battery terminal to reset the ECU, and when that didn't work, we checked the sensor-related fuses in the fuse box. Then, we measured the continuity of the wiring in sections and discovered, using a jumper wire test, that the wiring harness under the passenger floor mat had been worn through by the floor mat. Temporarily wrapping it with electrical tape made the fault disappear, but we ultimately replaced the entire wiring harness to completely resolve the issue. I recommend that fellow car enthusiasts pay attention not to crush cables when modifying floor mats.

[NolanFitz]

Fault code P2138 is a relatively common electronic issue in Dongfeng Nissan vehicles, with its core being signal voltage mismatch. In the electronic throttle system, when pressing the accelerator pedal, the two sets of sensors should output synchronously increasing voltages. However, if the onboard computer detects a voltage difference exceeding 0.5V, it will trigger the warning light. Potential culprits include: worn potentiometers inside the sensors, electromagnetic interference in wiring harnesses, or throttle servo motor failure. My neighbor's Sylphy had to replace the entire pedal assembly for this reason, costing approximately 400 RMB. During repairs, remember to clean the throttle body simultaneously as grease buildup can affect signal accuracy. Routinely avoid installing substandard electronic devices in the car, as power interference may cause false alarms.