P0268: Cylinder 3 injector high feedback under an on command

The GM P0268 row describes short-to-power detection on the cylinder 3 injector's low-side circuit. The driver is checked while commanded on, using voltage feedback outside the controller's expected range. The code therefore addresses electrical response rather than injector delivery accuracy.

Use command and supply as context

The test needs battery voltage of at least 11 volts and appropriate P062B injector-control status. Its count is ten failures out of twenty observations, sampled every 100 milliseconds, with Type A reporting. Retain those conditions when evaluating a stored event that is no longer present.

An on-state high result is distinct from a normal off-state output voltage. Any measurement or captured trace must be interpreted against the actual command and driver design. The code alone cannot identify the short's physical location.

Unresolved numeric wording

The source's threshold cell contains a poorly formed amperage comparison that does not clearly match its voltage-based description. It is not reproduced here as a usable current limit. Confirm the approved controller-specific threshold before performing workshop tests.

Identify cylinder 3 and the correct driver pins through vehicle-specific information, then follow the professional direct-injection electrical procedure. A passing completed on-state diagnostic is stronger verification than a brief normal idle. This source supports the electrical failure mode and counting logic, while its disputed numeric detail remains marked for review.

Source and applicability

This explanation is limited to the 2025 GM 25OBDG03A monitor on page 231. Its thresholds are calibration examples, not universal specifications. Confirm the vehicle, engine and controller procedure before applying them.