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:
Special Tool(s) /
General Equipment
Resistance Spotwelding Equipment
Spherical Cutter
Grinder
Knife
Spot Weld Drill Bit
Locking Pliers
Materials
Name
Specification
Metal Bonding AdhesiveTA-1, TA-1-B, 3M™ 08115, LORD Fusor® 108B
-
Seam SealerTA-2-B, 3M™ 08308, LORD Fusor® 803DTM
-
Flexible Foam Repair3M™ 08463, LORD Fuso..
Removal
NOTE:
Removal steps in this procedure may contain installation details.
WARNING:
Before beginning any service procedure in this
section, refer to Safety Warnings in section 100-00 General Information.
Failure to follow this instruction may result in serious personal
injury.
Refer to: Gasoline and Gasoline-Ethanol Fuel Systems Health and Safety Precautions (100..