P2269: Fuel conductivity is outside the sensor’s normal fuel range

P2269 identifies a high-conductivity fuel condition in the reviewed GM fuel-tank-zone-module system. Water in fuel is the example given by the source, but the monitor measures the sensor's conductivity-related frequency response rather than directly identifying a contaminant by chemical analysis.

A fuel-condition diagnosis

The flex-fuel sensor output must exceed 185 Hz. The source explicitly distinguishes this range from a sensor or wiring failure: high conductivity causes a substantial frequency increase and calls for investigation of the fuel condition.

That distinction prevents a consequential diagnostic error. Replacing the sensor solely because its frequency is high would disregard the very condition this diagnostic is designed to report. Conversely, the code alone is not a laboratory confirmation of the amount or type of contamination.

Confirm the documented architecture

This monitor applies to a vehicle with a fuel tank zone module and flex-fuel sensor. Ignition voltage must exceed 11 V, and specified module reset and communication fault groups must be absent. The controller needs 50 failures out of 63 samples on a 100-millisecond loop.

Preserve raw sensor frequency and module communication status when evaluating the event. A generic ethanol-percentage display may not show the out-of-range frequency used by this check.

Fuel sampling and any contaminated-fuel repair should follow the applicable professional service procedure. Verification requires the fuel-condition signal to return to its permitted behavior and the enabled monitor to complete without recurrence. The source lists Type A, one-trip behavior and gives no blanket sensor-replacement instruction.

Source and applicability

Use these facts only after confirming the documented system and calibration for the vehicle. GM diagnostic table, PDF page 627.