Jacobsen Eclipse 322, Repair Manual

Page: 102 / 336

4-28 4222983 Second Edition
ELECTRICAL
4
Theory of Operation and
Sub-Circuit Schematics
Horn and Work Light Circuit—Theory
of Operation
Power Circuit
Unswitched 48V power is available from stud 3 through
150A Fuse (F8) and 0.02 ohm resistor (R6) to key switch
terminal A and liquid crystal display (LCD) terminal
J11-8.
When the key switch is turned to the run position, 48 volts
is provided from key switch terminal B to liquid crystal
display (LCD) ignition terminal J11-5, powering up the
LCD.
With the LCD powered up, a ground is provided from the
LCD switched power contactor output terminal J11-10 to
the power distribution unit (PDU) terminal J1-4. With a
ground provided to J1-4, the 12 and 48 volt switched
power contactors are energized.
With the PDU 12 volt switched power contactor
energized, 12 volts is provided through 0.02 ohm resistor
(R12) to the main control unit (MCU) 12 volt power input
terminal (J2-8). PDU terminal J1-5 also provides 12 volts
to splice E and then from splice E, 12 volts is provided to
MCU 12 volt power input terminal J2-6. With the PDU 48
volt switched power contactor energized, 48 volts is
provided to circuit breaker (F4) and MCU 48 volt power
input terminal J2-7, powering up the MCU.
48 volts is also provided from circuit breaker (F4) to
splice A. From splice A, 48 volts is supplied to work light
terminal J28-1 and to optional OPS work light terminal
J123-2.
Voltage is provided from the LCD 12 volt power supply
terminal J11-6 to splice G. Splice G provides voltage to
the left reel enable switch. The left reel enable switch
provides voltage to the center reel enable switch. The
center reel switch provides voltage to the right reel
switch. The right reel switch provides voltage to the mow
switch. The mow switch provides voltage to the horn. The
horn switch provides voltage to the light switch.
Horn Circuit
When the horn switch is in the on position, 12 volts is
provided to the LCD horn switch input terminal J12-10,
activating the input. With the input activated, the LCD
horn output terminal J11-9 provides a ground to horn
terminal J87-2, activating the horn.
Work Light Circuit
When the work light switch is in the on position, 12 volts
is provided to LCD work light switch input terminal J12-9,
activating the input. With the input activated, the LCD
communicates the work light switch status to the main
control unit (MCU) through the controller area network
(CAN).
After receiving the work light switch status from the LCD,
the main control unit (MCU) work light output terminal
J3-5 provides a controlled ground to work light terminal
J28-2, turning on the light.
Work light output terminal J3-5 also provides a controlled
ground to optional OPS work light terminal J123-1.