CLK 430 (208.370) V8-4.3L (113.943) (1999)
Horn: Description and Operation
Function
Function
The fanfare switch (S4/2) is connected to the electronic ignition switch (EIS) control module (N73) by the horn/airbag clock spring contact (A45).
When the fanfare switch (S4/2) is actuated the corresponding input on the electronic ignition switch (EIS) control module (N73) is connected to ground.
If the starter switch is at least in position "1", the electronic ignition switch (EIS) control module (N73) transmits a message to actuate the fanfare horns
(HZ) to the driver-side signal acquisition and actuation module (SAM) (N10/1) via the CAN data buses.
The driver-side signal acquisition and actuation module (SAM) (N10/1) actuates the fanfare relay (K40/2k6). This relay is located on the driver-side fuse
and relay module (K40/2). It switches the fanfare horns (H2) to circuit 30 and the horns honk.
Notes
One lead from the fanfare horns (H2) is always connected to ground so that actuation is always accomplished by connection to circuit 30 (via K40/2k6).
The coil of the fanfare relay (K40/2k6) is permanently connected to circuit 15R so that when the fanfare horns (H2) are actuated the other connection is
connected to ground by the driver-side signal acquisition and actuation module (SAM) (N10/1).
Diagnosis
Diagnosis can be accomplished with the HHT and the diagnosis manual.