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 Door Lock Control Switch - Removal and Installation
NOTE: LH side shown, RH side similar.   Item Part Number Description 1 14028 Door lock switch 2 7822601 Front interior door handle Removal and Installation Remove the front interior door handle. For additional information, refer ...