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 Temperature Blend Door Actuator
  Item Part Number Description 1 — Temperature blend door actuator electrical connector (part of 18B604) 2 — Temperature blend door actuator screw (2 required) 3 19E616 Temperature blend door actuator (5-pin) Re ...