New-York tribune., 1918-08-18
There Is No Need to
Motor Your Way
In Darkness
By William H. Stewart. |r.

One Of the most annoying occur
rences while driving at night is to
have one Or more Of the lights 90 out.
The causes of this trouble are many
and varied, but a little knowledge of
the lighting system and a little ex-
perimenting will soon equip the aver
age motorist with sufficient command
OF the. system to locate all ordinary
troubles. He must first of all famil-
| iarize himself with the wires neces-
sary to carry the current from the
battery to the lamps. leaving the rest
of the system for later study. If the
instruction book that comes with the
car is available it will be of great
assistance, but this much of the sys-
tenn may be learned without it.
Can You Find These?
He must begin by locating the fol-
lowing: First, the battery, which may
be on the running board, under the
seat or slung on the frame, usually
under the floor boards; second, the
ammcter, which is carried on the dash
or instrument board; third, the SWITCH
on steering column or on the instru-
ment board near the ammeyer; fourth
the fuse box, which is usually near
the switch or under the hood, and,
fifth. the various lights.
The operator should now trace the
path Of the current from the bat
terry to lamps and back again, using
the diagram in the instruction book
if possible. Start at the battery and
The ammeter indicates whether the
battery is charging or discharging, and
80 is the first piece of apparatus to
be reached. The current now passes
to the switch, with which the fuse
block is usually closely associated.
The fuses ar. short lengths of fine
wire incased in glass. The wire is
made of lead and tin and melts at q
low temperature. If a short circuit
occurs on any line leading to lamp
the heavy rush of current is too great
for the fuse, which melts and breaks
the circuit, stopping, the current and
Of current were allowed to continue
the battery would be discharged and
ruined or the wires would become red
hot, with the possibility of setting fire
to some part of the car.
Tracing to the Lamps
Having located the switch and fuses
it should be an easy matter to trace
the current TO the lamps. Some sys-
TENS ground the currenc at the lamps
and it returns BY way of the frame of
the car This is known as the ''single
wire" system. Other systems provide
f,.r, f<, +cl, and
are known as "two-wire" systems. This
is easily determined by noting whether
the wire from switch to lamp is single
or double. This is an important detail
when ii comes to tracing the current
while looking for short circuits, otc
BY tracing both wires from the battery
one will be found grounded to the
frame.
In case all the lights go out we look
for some trouble at the battery, such
as a loose wire or terminal, or q short
circuit on some part Of the wires lead
ing from the battery. We follow along
the line by the ammeter, looking for
loose or broken wires or short circuits,
until we come to the switcn. 1t must
be evident that any trouble which af-
tccts the whole system must be on a
part Of circuit common to all the
lights. We do not suspect worn out
battery. as this trouble usually comes
on gradually and gives ample warning
by the lights being dim, Frightening as
the engine speeds up.
When One Light Goes Out
If only one light goes out VIC immc-
diat"ly inspect for defective light
bulb or see if the controlling fuse
has blown. If it has there is probably
a short circuit on that line or else the
fuse may have worn out DO not re-
place the burned out fuse until the
short has been found and removed. IF
the fuse is intact there is a break
somewhere on the line to the light.
probably a loose terminal
IT. light hickcrs-that is, goes on
ana OF intcrmlttently~that indicates
loose connection. Do not confuse this
W'th the case Of a weak battery, when
the iight rises and falls with the speed