OBD-II code · Powertrain (generic, extended)

P2266 Water in Fuel Sensor A Circuit Low

The water-in-fuel sensor at the diesel fuel filter reads below lower plausibility — short to ground. The sensor warns the driver to drain the filter when condensate accumulates.

Is it safe to drive with P2266?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyShort to ground
  • Less likelyConnector pins corroded - high contact resistance
  • Less likelyHarness chafing through insulation

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.3–1.5 h
Emissions test
Usually unaffected
Parts involved
Water In Fuel Sensor, Fuel Filter

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.