Starting And Charging System - Volvo VNL Service Manual

Group 30 Electrical System—VNL, VNM

Starting and Charging System

Battery Power Supply
Power is supplied from the batteries to the starter sole-
noid, then from the starter solenoid battery post via wires 1
and 1-A. (Note that each of these wires contains a fusible
link.) Wire I feeds cab main power stud 1, and 1-A feeds
cab main power stud 2.
The batteries also supply constant power to the alternator
via the starter solenoid. The starter solenoid post is con-
nected directly to the battery by wire 8, which senses the
battery voltage and energizes the alternator for charging
the batteries.
•
Stud 1 powers the Battery Maxi-fuse bus bar. From
this bus bar a Battery Maxi-fuse feeds 1-F to the the
fuse bus bar for fuse positions 21–24.
Also from the Battery Maxi-fuse bus bar, a Battery
Maxi-fuse feeds 1-D to the fuse bus bar for fuse
positions 17–20. Another Battery Maxi-fuse feeds 1-
C to the fuse bus bar for fuse positions 25–32.
Also from stud 1, wire 1-E goes to the Accessory
Power Relay.
•
From stud 2, wire 1-A goes to the Ignition Power
Relay. From wire 1-A, 1-B sends battery power to
bus bar fuse positions 41–48.
Accessory Supply
•
From fuse 15, wire 243–A supplies constant battery
power to the ignition switch.
•
When the ignition switch is switched to the ACCES-
SORY position, the 195 wire energizes the Acces-
sory Power Relay. The relay supplies power to wire
195–A for the bus bar for the Accessory fuse posi-
tions 33–40.
•
Ground wire 0R-N provides a ground connection
from the Accessory Power Relay to the Ignition
Power Relay. From the Ignition Power Relay, ground
connection 0R-M goes to a passenger side interior
ground stud (see section in this manual on Electrical
Pass-through for Cab Wiring, Power and Ground ).
18
A Pass-through for main cab wiring
Main Cab Electrical Pass-Through and Ground
Studs (driver side engine compartment)
Design and Function
W3000827