P02D5: cylinder 5 upper-limit SQP adaptation

The cited P02D5 entry monitors cylinder 5 for an injector energizing-time correction beyond the SQP maximum. This is an adaptation-authority fault rather than a direct electrical continuity result.

What can produce the stored finding

During diesel fuel cut-off, SQP commands a small fuel quantity and infers actual quantity from rail-pressure drop. As learned corrections enter the map, the controller evaluates them against an upper calibration boundary. The page provides the unit, microseconds, but not a numeric maximum.

Saturation is tracked for the individual rail-pressure levels. At least one saturated entry is sufficient for the stated diagnosis. That makes a pressure-specific failure compatible with apparently acceptable learning elsewhere; examining only the average or one live point can conceal the relevant evidence.

Resolve the wording before applying it

The source's maximum heading, greater-than criterion and maximum-threshold name are consistent. Several narrative sentences nevertheless say “minimum authority.” Those inconsistent sentences are not a reason to reverse the comparison.

Verification needs a valid SQP learning event with management and authority monitoring enabled, plus confirmation that relevant stored entries are no longer saturated. The source lists Type B reporting over two trips. It does not prescribe a replacement injector, prove overfueling or authorize invasive fuel-pressure testing. The next service decision should follow the applicable vehicle-specific diagnostic procedure.

Source and applicability

2025 GM 25OBDG04B diagnostic parameter tables; the cited monitor only. Vehicle, engine and calibration applicability must be confirmed separately. These tables describe detection logic, not a complete repair procedure or a component replacement verdict. gm-2025-04b, PDF page 1155.