P0200
Injector Circuit/Open.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 2
- AreaFuel and air metering (injector circuit)
- 00
- FaultThe specific fault in that area
What it means
P0200 is the generic code for a fault in the fuel injector circuit, reported as an open circuit. The engine control unit drives the injectors and monitors the circuit, and it has seen a voltage or current that suggests an injector or its wiring is not completing the circuit. Which injector or bank is affected, and how the circuit is monitored, depends on the make, model and engine.
Symptoms
- Engine warning light on
- Misfire or rough running, especially at idle
- Hesitation or loss of power under load
- Hard starting or a long crank
- Engine cutting out or stalling
- Poor fuel economy
Possible causes
- Open circuit or high resistance in an injector coillikely
- Damaged, chafed or broken injector wiringlikely
- Corroded, loose or damaged injector connector terminalslikely
- Poor power supply or earth to the injector circuit, such as a relay, fuse or earth point faultpossible
- Fault in the injector driver within the engine control unitrare
- Wiring harness damage from heat, vibration or previous repair workpossible
How to diagnose
- Read all stored codes and the freeze frame data to see engine speed, load and temperature when the fault set, and note any misfire codes that point to a specific cylinder.
- Clear the code and see how quickly it returns, noting whether it appears at start-up, at idle or only under certain conditions.
- Visually inspect the injector connectors and the harness for corrosion, bent or pushed-back pins, chafing, heat damage and signs of previous repairs.
- With the engine running, check for a cylinder that is not firing, and check whether each injector is clicking or pulsing using a suitable listening method.
- Measure the resistance of each injector against the manufacturer's specification, with the connector unplugged and the engine cold.
- Check the injector supply voltage and earth or driver signal at the connector, using the wiring diagram for the specific model and engine.
- Wiggle test the harness with the engine running or the circuit being monitored to find any intermittent break.
- Check the relevant fuses, relays and earth points, then test the wiring continuity back to the control unit before suspecting the unit itself.
How to fix
- Replace any injector that has an open coil or out-of-specification resistance, following the model-specific procedure.
- Repair or replace damaged wiring, using proper soldered or crimped and sealed repairs.
- Clean, repair or replace corroded or damaged connectors and terminals.
- Restore a faulty supply, relay, fuse or earth connection.
- If the wiring and injectors are proven good, have the control unit tested and repaired or replaced by a qualified specialist.
Can I keep driving?
Medium severity
The car can usually be driven a short distance to get it repaired, but expect poor running and possible cut-outs. Avoid prolonged driving, as a dead cylinder can cause unburnt fuel to reach the catalytic converter and damage it.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.