P2147: Injector 1 high-side circuit indicates a short to ground

P2147 carries a generic group A injector-supply-low title, but the reviewed GM table assigns it to injector 1's high-side circuit. That OEM mapping is specific to the documented implementation and should not be extended to every engine using the generic code.

An on-state electrical test

The output driver evaluates voltage while injector power is commanded on. A response outside its permitted range indicates a short-to-ground condition. This is evidence about the power-driving circuit, not a direct test of injector spray, fuel delivery or cylinder combustion.

The driver specification includes a 25-amp current criterion, but the summary is not a service instruction to apply or draw that current. Use the applicable diagnostic procedure and suitable equipment for the injector circuit.

Read the prerequisites before drawing conclusions

Battery voltage must be at least 11 V, and the row excludes the specified P062B failure states. The decision requires 10 failing samples out of 20, taken every 100 milliseconds. Thus a single low-voltage instant outside an enabled command window does not reproduce the onboard decision.

If several injector faults are recorded, retain their exact circuit identities and command states instead of treating the group label as proof of a shared mechanical injector problem. For this row, verification must show acceptable injector 1 high-side response when commanded on, followed by a completed monitor without recurrence. The documented result is Type A and one trip; it does not locate a damaged wire or identify a replacement component.

Source and applicability

The thresholds and component mapping apply only to the documented monitor, pending vehicle and calibration confirmation. GM diagnostic table, PDF page 603.