Fuel Injector Group "A" Supply Voltage Circuit Low
P2147 indicates the engine control module detected low voltage in the Fuel Injector Group A control circuit. This means the injectors in Group A (typically Bank 1 or a specific cylinder bank) are not receiving adequate electrical supply to operate properly, preventing normal fuel delivery and engine operation.
What You Might Notice
- Engine misfires or rough idle
- Reduced fuel economy
- Hard starting or no start condition
- Loss of power during acceleration
- Check engine light illuminated
Most Common Causes
- 1
Faulty fuel injector driver circuit
The injector driver module or relay controlling Group A injectors may be failing, preventing proper voltage delivery to the injector coils.
- 2
Corroded or loose electrical connections
Corrosion, loose terminals, or damaged wiring in the fuel injector harness or connector can reduce voltage supply to the injectors.
- 3
Defective fuel injectors
One or more fuel injectors in Group A may have internal electrical faults causing high resistance or open circuit conditions.
- 4
PCM or ECU malfunction
The engine control module may have a faulty injector driver circuit or software issue preventing proper voltage output to the injector group.
How to Diagnose It
- 1
Check Faulty fuel injector driver circuit — The injector driver module or relay controlling Group A injectors may be failing, preventing proper voltage delivery to the injector coils.
- 2
Check Corroded or loose electrical connections — Corrosion, loose terminals, or damaged wiring in the fuel injector harness or connector can reduce voltage supply to the injectors.
- 3
Check Defective fuel injectors — One or more fuel injectors in Group A may have internal electrical faults causing high resistance or open circuit conditions.
- 4
Check PCM or ECU malfunction — The engine control module may have a faulty injector driver circuit or software issue preventing proper voltage output to the injector group.
How to Fix It
- 1
Inspect and clean fuel injector connectors
Disconnect the fuel injector harness connectors for Group A and inspect for corrosion, pitting, or looseness. Clean with contact cleaner and reconnect firmly, ensuring secure seating.
- 2
Test injector driver circuit voltage
Using a multimeter or oscilloscope, measure the voltage at the fuel injector connectors with the key on. Verify the PCM is supplying the correct control voltage to Group A injectors.
- 3
Replace faulty fuel injectors
If voltage is present but injectors are not responding, test individual injectors for resistance. Replace any injectors in Group A with resistance values outside manufacturer specifications.
- 4
Replace injector driver module or PCM
If all injectors test good and proper harness connections are confirmed, the fault lies in the injector driver circuit within the PCM. This may require professional module reprogramming or replacement.
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