Nissan U1025-00 [2021] Jun 2026

(specifically for variable geometry turbochargers). On models like the Pathfinder Navara (NP300) , or other vehicles with the

The engine may bog down or refuse to rev beyond 2,000 RPM.

A lot of DIYers see “ECM” in the code definition and immediately buy a used engine computer. In 90% of U1025-00 cases, the modules are perfectly fine. The problem is the connection between them.

When this code triggers, the vehicle usually enters a "Limp Home" mode to protect the engine. Common symptoms include: nissan u1025-00

This is a "U" code, which indicates a network communication issue. Specifically, the Engine Control Module (ECM) has lost communication with the electronic turbocharger actuator (sometimes called the VNT or Variable Nozzle Turbine actuator). The "-00" suffix typically denotes no sub-type information is available, meaning it is a general failure.

This is a communication-based Diagnostic Trouble Code (DTC) where the Engine Control Module (ECM) loses contact with the electronic turbocharger actuator. Primary Symptoms

Because the turbo sits low or exposed to elements in many Nissan engine configurations, the wiring harness routing to the actuator plug frequently degrades. Corroded pins, frayed signal wires, or an open circuit in the power/ground supply will block transmission. 3. Mechanical Jamming of VGT Vanes (specifically for variable geometry turbochargers)

Specifically at the ECM, TCM, or CAN Gateway.

If power and ground are stable, use an oscilloscope or a high-end scan tool to check for active signal pulses on the CAN High and CAN Low communication lines. 3. Test Mechanical Actuation Freedom

Check the harness going to the transmission for chafing against the body. In 90% of U1025-00 cases, the modules are perfectly fine

When this code is active, your Nissan will behave differently. Common signs include:

Sometimes the code is a "ghost" code from a momentary power fluctuation. Use an OBD-II scanner to clear all codes. Action: Test drive to see if the U1025-00 returns. Conclusion

🛑 : Since the turbo vanes cannot open or close to build boost, the car will feel incredibly sluggish, struggling on inclines.

: This fault is regularly paired with code P102B (Turbocharger Boost Control Circuit) or P1021 (Actuator Circuit Fault). Primary Causes of the Error

: If the internal vanes of the turbocharger are stuck due to carbon buildup, the actuator may struggle to move them, leading to a communication or position error.