What it means
The ECU detects an open or missing supply voltage on injector group A. The injectors of this bank cannot be energized; the affected cylinders may not fire and the engine runs rough or stalls.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
Injector group A shares a supply circuit that provides power for the group’s injectors, while the ECU controls when each injector opens. This code sets when the ECU detects that group A’s supply circuit is open or its expected voltage is missing, so the affected injectors may not operate.
Common causes
Most likely first.
- Blown injector fuse
- Faulty injector supply relay
- Open in supply wiring
Symptoms
- Check engine light on
- Misfire or rough idle on the affected cylinder
- Increased fuel consumption
- Possible fuel smell or smoke from exhaust
How to diagnose it
- Record freeze-frame data and check for related injector, power-supply, or misfire codes to see when group A lost power.
- Use live data, if available, to confirm the fault is associated with injector group A and note which cylinders are misfiring.
- With the ignition off, inspect group A’s fuse, relay, connectors, and supply wiring for a blown fuse, loose connection, damage, or corrosion.
- Check for supply voltage at the group A circuit and across the fuse and relay under the conditions specified by the manufacturer.
- If power is missing, trace continuity through the group A supply wiring and relay circuit to locate the open; use the manufacturer’s wiring diagram.
Common fixes
- Replace a blown injector group A fuse after checking for a short or overload.
- Repair an open, damaged, or corroded group A supply wire or connector.
- Replace a faulty injector supply relay if its input is present but its output is missing.
- Clear the code and verify group A supply and engine operation.
Can I keep driving?
Avoid driving if the engine is running rough, misfiring, or stalling; unburned fuel can damage the catalytic converter and the vehicle may lose power unexpectedly. Arrange prompt diagnosis, especially if there is fuel smell or exhaust smoke.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.