OBD-II · Engine and powertrain (P)
P2147
Fuel injector group A supply voltage circuit low
What it means
Many engine computers power the injectors in groups (for example two cylinders per group). The supply voltage to injector group A is too low, usually a short to ground. Which cylinders are in group A depends on the engine.
Symptoms
- misfire or cut-out on two or more cylinders
- rough running and loss of power
- possible no start
- engine warning light
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | shorted injector or injector wiring pulling the group supply down |
| 02 | chafed injector harness |
| 03 | oil or water in an injector connector |
| 04 | engine computer injector driver fault |
What to check, step by step
- 01Identify the affected injector group and its circuit from the engine-specific wiring diagram.
- 02Switch off and follow OEM shutdown/discharge precautions before touching or disconnecting injector wiring. Never unplug injectors while the engine is running.
- 03Inspect connectors and the harness. With the ECU and injectors isolated as specified, test continuity and shorts to ground, supply and adjacent circuits.
- 04Test injectors with the OEM procedure and equipment suitable for their solenoid or piezo design; do not infer failure simply because a code changes when one is unplugged.
- 05Check relevant ECU power and grounds; consider a driver fault only after wiring and injectors pass the specified tests.