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 Distortion
Special Tool(s) Feeler Gauge Set 303-D027 (D81L-4201-A) or equivalent NOTE: Refer to the appropriate Section 303-01 for the specification. NOTE: Make sure all cylinder head surfaces are clear of any gasket material, silicone sealant, oil and coolant. The cyl ...