P25B1: Fuel-level sensor B stuck monitoring uses consumption history

P25B1 is the fuel-level sensor B stuck result in Ford's monitor, represented as P2065_2A. It evaluates whether the level input changes appropriately relative to calculated fuel consumed. This is a different question from whether the B signal is electrically high, low or noisy.

The indicated tank region changes the comparison

Ford's example allows different consumed-capacity versus level-change disagreements depending on the indication. The threshold is over 60 percent above a 90-percent indication, over 30 percent below 10 percent, and over 25 percent between those regions. Applying only the middle-region value to a near-full reading would change the documented test.

Monitoring between 15 and 85 percent can take approximately 100–120 miles in the cited example. That duration explains why a short observation of an unchanged level is not a complete verification; it is not a universal road-test instruction.

Preserve B identity instead of guessing a sender location

The source separately lists A stuck and A-or-B stuck categories. P25B1 identifies B, but the summary does not establish the physical tank layout or which side a B sender occupies on the reader's vehicle.

A useful record retains the B input, calculated fuel use and level history. A plausible electrical value cannot alone establish that this functional comparison passed. The applicable vehicle procedure must verify the actual sensing arrangement and identify the cause before a sender or tank component is replaced.

Source and applicability

Ford 2024–2025 gasoline OBD operation summary, July 16 2024 revision; only the cited monitor and transmission architectures. No individual vehicle fitment or universal calibration is inferred. Ford PDF, page 18. Ford PDF, page 19.