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 Driver Airbag
  Item Part Number Description 1 — Horn switch electrical connector 2 043B13 Driver air bag module 3 — Driver air bag module electrical connectors (part of 043B13) 4 — Horn switch electrical connector ...