P02B5: Cylinder 7 leakage is a monitor conclusion, not a direct leak measurement

P02B5 identifies the cylinder 7 branch of GM’s injector failure-open assessment. The title “injector leaking” is a concise result label. The underlying monitor reaches that result indirectly from combustion and fuel-pressure-control behavior.

The controller’s two-part evidence

Cylinder 7’s misfire counter must exceed 100, and the rail-pressure-control minimum-error flag must be true. Electrical failures of the high-pressure injectors must be absent. The electrical exclusion helps keep a mechanical-failure inference separate from a known injector circuit problem.

The five-second evaluation is restricted to an engine-speed band above 1,520 and below 6,000 rpm, with relative air charge below 100 percent. Statistical inhibition and the common enable and inhibit conditions still apply. Reporting is classified as two-trip.

Avoid converting inference into certainty

A diagnostic record should retain the two underlying observations instead of only the summary label. That lets the service process examine whether the cylinder-specific and shared-rail evidence agree with the suspected failure mode.

The neighboring injector-leakage codes use the same logic for other cylinder numbers; this one selects cylinder 7. The source does not establish cylinder location, injector part number or a repair outcome. Confirm applicability and follow the proper high-pressure fuel diagnostic procedure. An absence of the code outside its eligible window is not evidence that a suspected leak has been disproved.

Source and applicability

This explanation covers the cited GM monitor, not every vehicle carrying this code. The application-matrix filename does not resolve cleanly to this file, so no model or engine fitment is assigned. GM diagnostic table, PDF page 709.