U0665Lost Communication With Fuel Rail Pressure Sensor Bank 2
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Engines with one fuel rail per cylinder bank may give each rail its own pressure sensor, and newer ones send the reading digitally via SENT. U0665 says the controller has lost the bank 2 sensor's data. GM's 23OBDG07 and 24OBDG07 tables pair it with GM's own code U101C: path 1 trips when the signal line stays at high level, path 2 when it stays low, each after 0.5 s and within one trip. An out-of-range raw value from the same sensor is logged separately (GM P312B), and the plausibility tests of P01BF run on top. The bank 1 sensor follows the same logic with U0625 and U101B. Analog bank 2 circuit faults are P01BE to P01C2. Without a rail pressure value the controller falls back to a substitute model; reduced power and rough running are possible.
- What you may notice
- Check engine light after one trip
- Reduced power, hesitation or rough running
- GM-specific code U101C stored alongside
- Likely causes
- LikelyBank 2 sensor signal wire open or shorted to ground or voltage
- PossibleFuel-soaked, corroded or loose sensor connector
- PossibleRail pressure sensor electronics on bank 2 failed
- RareEngine controller SENT input faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.