Steady light versus flashing light
A steady amber light means the engine control unit has stored a fault and is often still running normally. A flashing light usually means an active misfire, which can destroy a catalytic converter within minutes. Flashing means stop driving and call us.
Common causes
- Misfires from ignition coils, plugs or injectors
- Air leaks and mass airflow sensor faults
- EGR and DPF faults on diesels
- Faulty sensors — lambda, temperature, pressure
- Turbo boost control problems
- Wiring, connector and earth faults
Why a code reader is not a diagnosis
A code identifies a circuit or a symptom, not a broken part. Replacing whatever the code names is how people spend money twice. Live data, wiring checks and physical testing are what confirm the cause.
What to do next
- Note when it appeared and what the car was doing
- Check for loss of power, noise, smoke or temperature changes
- Avoid long journeys until it is read
- Book a diagnostic appointment rather than clearing the code