Ford Focus Service Manual: Horn

Body Electrical

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Horn - Description and Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM) . The horn system consists of the following components: Horn switch Horn relay (part of the SJB ) ...

More about Ford Focus:

Ford Focus Connecting an external device
WARNING: Make sure the external device is securely mounted within the vehicle, and that trailing connections do not obstruct any of the driving controls. External devices may be connected using the auxiliary input socket and the USB port. See Auxiliary input (AUX IN) socket. See USB port. ...