P2666Fuel Shutoff Valve B Control Circuit Low
- Generic OBD-II code · Powertrain
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2666 is stored when the control line of fuel shut-off valve B sits at too low a voltage, the typical sign of a short to ground between module and valve or inside the coil. Depending on how the driver is built, the valve may then open whenever the ignition is on, or the module switches the output off for protection. No manufacturer documents P2666 publicly. In bi-fuel vehicles such as GM's CNG Impala, the ECM controls normally closed cut-off valves on the gas side and changes over to gasoline as soon as it detects a problem in one fuel system; GM's Silverado and Sierra CNG models signal such errors with a rapidly flashing fuel indicator. P2665 is the open circuit and P2667 the short to voltage on the same valve, P0006 the low fault of valve A.
- What you may notice
- Gas mode switched off, engine runs on gasoline
- Fuel mode lamp flashes rapidly
- Likely causes
- LikelyControl wire chafed through and shorted to ground
- PossibleValve coil shorted internally
- RareWater ingress in the valve connector
- Inspection (ITP)
- Can matter for the ITP: it concerns the emissions system.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.