What it means
Cylinder 3 Injector Circuit High: the signal voltage is above the expected range. This affects fueling of the associated cylinders.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The engine control module monitors the electrical circuit that operates the cylinder 3 fuel injector. This code sets when the circuit signal is higher than expected, which can point to a short to supply or another electrical fault affecting cylinder 3 fueling.
Common causes
Most likely first.
- Injector circuit shorted to supply
- Wiring or connector fault
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine light
- Rough idle or misfire
- Reduced power
- Increased fuel consumption
How to diagnose it
- Review freeze-frame data and cylinder-specific misfire information to identify when the cylinder 3 fault occurs.
- Inspect the cylinder 3 injector connector and harness for corrosion, loose pins, chafing, or contact with a power feed.
- With the circuit safely isolated according to the wiring diagram, check the cylinder 3 injector and harness for an unintended connection to supply.
- Check connector fit and wiring continuity through the cylinder 3 injector circuit, paying attention to damaged wires and corroded pins.
- If the injector and harness pass, test the module's cylinder 3 injector control circuit using the manufacturer's procedure.
Common fixes
- Clean and secure corroded or loose cylinder 3 injector connector pins.
- Repair wiring shorted to a power supply in the cylinder 3 injector circuit.
- Replace a damaged cylinder 3 injector if testing confirms it is faulty.
- Repair the injector control circuit or module if circuit tests identify it as the source.
Can I keep driving?
If the engine runs smoothly, limit driving to a short trip for diagnosis and avoid hard acceleration. Stop if it misfires, loses power, or smells strongly of fuel, since poor fueling can raise emissions and damage the catalytic converter.
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.