The P0259 code on your 2023 Mercedes-Benz E-Class indicates a high input from the injection pump rotor position sensor circuit. Mercedes offers both gasoline and diesel variants globally, so engine type determines this code's relevance.
2023 E-Class Engine Configuration
In North America, the 2023 E-Class primarily offers gasoline engines: the E350's 2.0L turbo four-cylinder and the E450's 3.0L turbo inline-6, plus AMG variants. The E300d diesel is available in European and other markets. P0259 is specific to diesel injection pump systems.
Diesel E-Class Diagnosis
For diesel-equipped E-Class models, P0259 indicates higher-than-expected voltage from the pump position sensor. This typically results from an open signal circuit, disconnected sensor, or sensor failing in a high-output state. The sensor provides crucial timing information for precise injection control.
Gasoline Model Considerations
Mercedes' gasoline engines use different fuel system architecture without rotary injection pumps. If P0259 appears on a gasoline E-Class, verify using Mercedes XENTRY diagnostics. The code may be misread by generic tools or indicate a software anomaly requiring dealer verification.
Resolution Path
For diesels, test the sensor circuit for open conditions and verify sensor output. High readings often indicate broken wires or disconnected sensors. For gasoline models, dealer diagnostics can confirm whether the code is valid. Address any actual fuel delivery symptoms using gasoline-appropriate diagnostic procedures.