SECTION 06: ELECTRICAL
20
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version) – Sec 06 revised June 2017
DANGER
During charging of the batteries, an explosive
gas mixture forms in each cell. Part of this gas
escapes through the vent holes and may form
an explosive atmosphere around the battery
itself if ventilation is poor. This explosive gas
may remain in or around the battery for
several hours after it has been charged.
Sparks or flames can ignite this gas causing
an internal explosion, which may shatter the
battery.
1. Do not smoke near a battery which is
being charged or which has been recently
charged.
2. Do not break live circuits at battery
terminals because a spark usually occurs
at the point where a live circuit is broken.
Care must always be taken when
connecting or disconnecting booster leads
or cable clamps on chargers. Poor
connections are a common cause of
electric arcs, which cause explosions.
3. The electrical system on this vehicle is
negative ground. Installing the batteries
with the positive terminals grounded or
incorrect use of the booster battery and
jumper cables will result in serious
damage to the alternator, batteries and
battery cables.
The alligator clamps of the tester or charger
should make firm contact with the terminal
battery adapter.
Never clamp charger or tester
directly onto threaded studs or nuts.
FIGURE 20: ALLIGATOR CLAMPS
Warning
Always turn off the charger before connecting
or disconnecting to a battery.
Note
The charge rate must be doubled when the
batteries are charged by the booster block,
because of the series-parallel circuit.
DANGER
Do not use the “jump start boost” feature of an
off-board battery charger to jump start the
vehicle. This could damage the electrical
system.
2.6.1 Booster
Block
The booster block is located near the batteries in
the engine compartment on the R.H. side and is
accessible through the R.H. side door (Figure
21).
FIGURE 21: BOOSTER BLOCK
Both booster and discharged batteries should be
treated carefully when using jumper cables. A
vehicle with a discharged battery may be started
by using energy from a booster battery or the
battery from another vehicle.
DANGER
Jump starting may be dangerous and should
be attempted only if the following conditions
are met:
1. The booster battery or the battery in the
other vehicle must be of the same
voltage as the battery in the vehicle
being started, and must be negative
grounded.
2.
If the booster battery is in another
vehicle, that vehicle's engine must be
shut off before connecting and must
remain off during jump starting.
3. If the booster battery is a sealed-type
battery without filler openings or caps, its
test indicator must be dark or a green dot
