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 Cylinder Head Temperature (CHT) Sensor
  Item Part Number Description 1 9H589 Cylinder Head Temperature (CHT) sensor electrical connector 2 12A674 CHT sensor Removal and Installation Pull back the Cylinder Head Temperature (CHT) sensor cover and disconnect the elect ...