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 Airbag and Safety Belt Pretensioner Supplemental Restraint System (SRS)
Refer to the following illustrations for the servicable Supplemental Restraint System (SRS) components. Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Components — Illustration 1 of 2   Item Part Number Description 1 044A74 P ...