Textron JACOBSEN GP400, Technical/Repair Manual

Page: 66 / 354

4-14 4252490-Rev A
ELECTRICAL
4
Theory of Operation and
Sub-Circuit Schematics
Power Circuit—Theory of Operation
Reference electrical schematic. See Figures 4-1 through
4-5.
Unswitched Power Circuit
Unswitched power is provided from the battery positive
terminal to the starter motor battery terminal, and then
from the starter motor battery terminal to the alternator
battery terminal for diesel models or to the voltage
regulator DC output terminal on gasoline models.
Unswitched power is also available from the battery
positive terminal to splice 1. Splice 1 provides voltage to
glow plug relay terminal 30 through 40A fuse F7 for
diesel models.
Splice 1 provides unswitched power to the following:
• Fuse block terminal 7 (not used)
• Key switch terminal A
• Start relay terminal 30
• Fuel shutoff timer terminal 3 (diesel)
Switched Power Circuit
When the key switch is turned to the run position, voltage
is provided from key switch terminal B to splice 3. Splice
3 provides voltage to the following fuse block fuses:
• 10A fuse F2
• 20A fuse F3
• 10A fuse F4
• 10A fuse F5
• 15A fuse F6
The 10A fuse F2 provides voltage to the 12V air seat
connector J6.
The 20A fuse F3 provides voltage to the control module
terminals J1-2, J2-11 and J2-12, powering up the control
module. With the control module powered up, 5 volts is
provided from the control module 5V output terminal J1-8
to the following:
• Raise/lower switch terminals 1 and 6
• Seat switch
The 10A fuse F4 provides voltage to the following:
• Alternator field terminal (diesel)
• Fuel pump
• Paddle option connector J7-1
• Horn switch
• 3-Pin connector J4-1
• Mow switch
• Mow/transport switch
• Engine oil pressure light
• Hydraulic filter pressure light
• Engine temperature gauge (diesel)
The 10A fuse F5 provides voltage to the 12V accessory
socket.
The 15A fuse F6 provides voltage to the light switch.