P2767 Fault Code in 2007 Dodge Charger 5.7L: Input Shaft Speed Sensor Issue and Dealer Misdiagnosis
My 2007 Dodge Charger with a 5.7L engine has entered permanent limp mode, and the OBD2 diagnostic code P2767 is showing up. The code indicates a 'No Signal' from the Input Shaft Speed Sensor (N3). The dealer suggests replacing the conductor plate in the transmission plug, claiming it's the root cause. However, I've noticed that the input shaft speed sensor and the conductor plate are technically different components with distinct part numbers and pricing. After installing both the valve body sensor and the transmission plug sensor, the code persists and limp mode remains active. I'm seeking clarification: What diagnostic steps should be taken before replacing parts? The official trouble tree lists several potential causes: - (T72) Sensor Supply Voltage Circuit Open - (T71) Input Speed Sensor 2 (N3) Signal Circuit Open - (T71) Input Speed Sensor 2 (N3) Signal Circuit Short to Another Circuit - (T13) Sensor Ground Circuit Open or Short to Ground I believe the issue may lie in circuit integrity rather than a faulty sensor. A lab-grade oscilloscope would be ideal for verifying signal presence and waveform accuracy. Can anyone confirm whether I've missed any essential diagnostic checks before part replacement? Also, it's recommended to use original Dodge sensors—aftermarket parts often fail under load conditions.
The P2767 code indicates a 'No Signal' condition and points primarily to circuit-related issues. A lab scope is essential for verifying the presence and integrity of the signal waveform—this will quickly reveal whether the sensor is sending data or if there's a missing/abnormal signal. Before replacing any components, ensure all basic diagnostics have been exhausted: voltage supply checks, ground continuity tests, and circuit short-to-ground or short-to-other-circuit evaluations. The dealer’s suggestion to replace the conductor plate in the transmission plug lacks clear diagnostic support. Without evidence of a broken wire or open circuit, such a replacement is speculative. Possible causes include: - (T72) Sensor Supply Voltage Circuit Open - (T71) Input Speed Sensor 2 (N3) Signal Circuit Open - (T71) Input Speed Sensor 2 (N3) Signal Circuit Short to Another Circuit - (T13) Sensor Ground Circuit Open or Short to Ground Always use original Dodge sensors—aftermarket parts often fail under real-world conditions and may not meet OEM specifications. A proper diagnostic scan with a scope is the most reliable path forward.