Ford Focus Owners Manual: Principle of operation

Engine immobiliser

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Coded keys

Note: Do not shield your keys with metal objects. This may prevent the receiver from recognising your key as a valid one. Note: Have all of your remaining keys erased and recoded if you lose a key ...

More about Ford Focus:

Ford Focus Spark Plug Inspection
Inspect the spark plug for a bridged gap. Check for deposit build-up closing the gap between the electrodes. Deposits are caused by oil or carbon fouling. Install a new spark plug. Check for oil fouling. Check for wet, black deposits on the insulator ...