P2147
Fuel Injector Group A Supply Voltage Circuit Low
The supply voltage measured at injector group A is below the calibrated threshold. Either the supply is shorted to ground or the source voltage has collapsed during cranking or load.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Misfire or rough idle on the affected cylinder
- Increased fuel consumption
- Possible fuel smell or smoke from exhaust
Common causes
Ordered by how often each turns out to be the cause.
- Supply wire shorted to groundCommon
- Weak battery, low cranking voltagePossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Fuel Injector
- Injector Supply Relay
- Injector Wiring
P2147 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.