P2047: DEF dosing valve 1 open-circuit status

P2047 is the bank 1, unit 1 reductant-injector open-circuit code in the reviewed GM ECM table. It monitors the hardware interface's open-load diagnosis for the DEF dosing valve. The source does not use a measured flow deficit or catalyst-efficiency result to set this code.

An electrical status must be determinate

The hardware open-circuit state must explicitly indicate a fault. The same interface must first be different from an indeterminate state. That prerequisite separates a confirmed electrical indication from a diagnostic result that is not yet usable.

The engine need not be running: key-on operation can satisfy the power-state requirement. Cranking is excluded, however, and battery voltage must exceed 11 volts. Calibration must also enable the test. An observation made during cranking or with inadequate supply does not reproduce the published conditions.

Persistence and useful verification

GM requires 30 failing samples within 60 samples on a 100-millisecond time basis. The reporting class is Type A, one trip. This counter qualifies repeated hardware evidence; it does not locate an open connection or establish that the dosing valve itself is the failed part.

A useful confirmation reviews the unit 1 open-circuit status after it becomes determinate with the required supply present. Successful pressure buildup elsewhere in the reductant system is not a substitute for this valve's electrical check. The source gives no pinout, resistance specification or replacement procedure. The explanation is confined to the documented 2025 GM monitor until vehicle and dosing-system applicability are confirmed.

Source: GM monitor, PDF page 774.