Ford Fusion: Horn / Horn - System Operation and Component Description. Description and Operation
System Operation
System Diagram

Item |
Description |
1 |
BJB |
2 |
Horn Relay |
3 |
Horn Switch |
4 |
Clockspring |
5 |
SCCM |
6 |
BCM |
7 |
Horn |
Horn Operation
The
horn switch consists of 2 sets of contacts separated by springs. The
lower set is connected to ground and the upper set is connected to the
horn signal circuit. When the driver airbag is pressed, it pushes down
on the upper set of contacts, collapsing the springs and allowing the
contacts to touch. When the contacts touch, it completes the circuit and
provides the ground signal, which is routed through the clockspring to
the SCCM and BCM. The BCM grounds the horn relay coil to energize the integrated relay in the BJB. When energized, the horn relay provides voltage to the horn, enabling the horn to sound.
DTC Chart
Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods (100-00 General Information, Description and Operation)...
Other information:
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General Equipment
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Adjustable Mounting Arm
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..
Overview
The
EEC system provides optimum control of the engine through the enhanced
capability of the powertrain control module (PCM). The EEC system also
has an on board diagnostic (OBD) monitoring system with features and
functions to meet federal regulations on exhaust emissions.
The
EEC system has two major divisions: hardware and software. The hardware
includes the PCM, sensors, swit..