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 Seat Position Sensor
  Item Part Number Description 1 — Seat position sensor electrical connector (part of 14A699) 2 14B416 Seat position sensor 3 — Seat position sensor lock tab Position the driver seat to the rearmost and maximum ...