P2668Fuel Mode Indicator Lamp Control Circuit
- Generic OBD-II code · Powertrain
- How the car detects it
- Bi-fuel vehicles tell the driver which fuel is in use through a small indicator, often built into the fuel selector button. On GM's 2016 Silverado and Sierra with CNG the light is off on gasoline, steady on natural gas, flashes once per second during a changeover and flashes about ten times per second when the CNG system has a fault; the 2015 Impala Bi-Fuel uses a similar light in its CNG switch. P2668 indicates that the module driving this lamp has found a fault in its control circuit, such as an open wire or a failed bulb or LED. No manufacturer documents the code publicly. Fuel switching itself is unaffected, but the driver loses the fuel mode display and the error warning. P26E2 and P26E3 are the low and high variants.
- What you may notice
- Fuel mode lamp stays dark in gas mode
- No flashing during fuel changeover or on errors
- Likely causes
- LikelyIndicator LED or bulb in the selector switch failed
- PossibleOpen wire or loose connector at the switch
- RareLamp driver in the control module defective
- Repair
- Easy · Often possible to do yourself.Typical cost: €30 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.