Powertrain, generic (extended)

P238D Water in Fuel Sensor B Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P238D reports that the signal of water-in-fuel sensor B sits above its valid range, usually from an open circuit, a disconnected sensor or a short to voltage. Stellantis case file S2214000004 documents it for 2022 Ram 2500, 3500, 4500 and 5500 trucks: the water warning lamp or message comes on at low mileage, and the cause is water that a pressure washer or similar spray drove into the plug of the filter housing on the frame rail. Technicians inspect both connector halves; corrosion means replacing filter housing and harness connector, plain water means drying, dielectric grease and a retest, with a new housing if the code returns. Stellantis stresses that P238D is not P238F, which reports actual water. P238C is the low counterpart.

Likely causes

Spray water in the connector at the chassis-mounted fuel filter
Corroded terminals on harness or filter housing side
Sensor in the filter housing failed
Open signal or ground wire

Symptoms

  • Water-in-fuel lamp or message on at low mileage
  • No water found when draining

Repair estimate

DifficultyEasyDIY possible
Parts and labour€0–400
Time0.3–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

water in fuel sensor b

Related codes

P238CP238AP238FP2267

References: static.nhtsa.gov, en.wikipedia.org.