Jacobsen AR3, Technical/Repair Manual

Page: 74 / 342

ELECTRICAL
4181384 First Edition 4-17
4
Theory of Operation and Sub
Circuit Schematics
Power Circuit—Theory of Operation
Unswitched Power Circuit
Unswitched power is available from the battery positive
terminal to the following components:
• 40A fuse F11
• Cab power connector X5, terminals 1 and 2
• Starter motor battery terminal
• 40A fuse F12
• Glow plug relay terminal 30
• 2A fuse F5
• Multi-function gauge terminal 8
• Key switch terminal 30
• Jump start terminal X8
The jump start terminal provides a more accessible place
to charge the battery or to jump start the machine.
Switched Power Circuit
When the key switch is turned to the run position, voltage
is available from key switch terminal AC to the following
components:
• 15A fuse F1
• 15A fuse F2
• 10A fuse F3
• 5A fuse F4
• 2A fuse F5
• 7.5A fuse F7
• 5A fuse F8
• 5A fuse F9
• 10A fuse F10
• Alternator excitation terminal
• Fuel pump
• Mow switch terminal 5
• Park brake switch terminal 8
• Brake solenoid
• Weight transfer switch terminal 5
• Engine oil pressure light
• Hydraulic filter light
• Setup switch
• Alternator light
With the key switch in the run position, current flows
through 10 amp fuse F10 to control module terminals 3
and 8, powering up the module. Current also flows to
multi-function gauge terminal 2, powering up the gauge.
5-Volt Power Circuit
With the control module powered up, the control module
now provides 5 volts to the following components:
• Seat switch
• Mow switch
• Park brake switch
• Raise/lower switch
The 5-volt power circuit is used to activate the control
module switch inputs when a switch contact is closed.