Buick LeSabre 1965 Service Manual page 625

ELECTRICAL SYSTEMS
DIRECTION SIGNAL 1 0 - 5 5
3. If horns still do not blow when
wire at mast jacket is grounded,
unplug double connector from
horn relay part of junction block
assembly. Then plug a known
good relay and junction block as-
sembly onto the connector and
press battery terminal of new
assembly against old junction
block battery terminal stud for a
source of current. Ground base
of new relay. Have helper try
blowing horns. If horns blow,
original relay is defective and
must be replaced.
4. If horns still will not blow
with substitute horn relay trouble
is elsewhere. Check wiring con-
nections and wiring throughout
horn circuit. See Figure 10-166
for wiring diagram.
b. Horns Will Not Stop
Blowing
1. Pull horn wire from connector
on wire that enters mast jacket
(tan wire). If horns stop blowing,
relay is OK, but horn control
circuit in jacket is grounded. If
horns do not stop blowing horn
relay control circuit is grounded.
Check horn wire and contacts in
mast jacket and steering wheel
if horns stopped blowing.
2. If horns still do not stop blow-
ing, unplug double connector from
horn relay. Then plug a known
good relay onto the connector and
make contact with junction block
stud.
3. If horns now stop blowing,
original relay contacts are stick-
ing and relay and junction block
assembly must be replaced. How-
ever, if horns still do not stop
blowing, c o n t r o l c i r c u i t is
grounded between relay and con-
nector on wire that enters jacket.
c. Horn Tone is Poor
If either horn blows only part of
the time or tone is poor, adjust
current draw at horn, subpara-
graph e.
d. Voltage Test at Horn
An improperly operating horn and
its wiring circuit can be tested by
connecting a voltmeter between
the horn terminal and ground and
noting the voltage while the horn
button is pressed. The voltage at
the horn gives an indication of
the cause of trouble as follows:
1. No voltage indicates trouble
in horn button, relay, wiring, or
ground.
2. Less than 7 volts indicates
trouble in wiring or excessive
current draw due. to short circuit
in horn.
3. Voltage between 7 and 11 in-
dicates that wiring is okay. Look
for sticking or improper adjust-
ment of horn.
4. Voltage above 11 indicates im-
proper adjustment or open circuit
in horn due to broken coil lead.
e. Adjustment of Horns
1. Remove horn from car.
2. Connect an ammeter in series
with horn and a fully charged
12 volt battery to measure cur-
rent draw while horn is blowing.
Current draw for each horn
either high or low note) should be
between 4.5 and 5.5 amperes at
12.0 volts.
3. Adjust to specified c u r r e n t
draw if necessary, by turning ad-
justing screw clockwise to de-
crease or counterclockwise to
increase current draw. Turn only
1/4 of a turn at a time. If adjust-
ment loosens screw excessively,
it may be staked with a prick
punch. See Figure 10-56.
Increasing the current draw in-
creases the horn volume. Too
much current will cause a high
cut-in voltage which will cause
a sputtering sound and may cause
horn to stick in cold weather.
4. After each horn has been ad-
justed individually, sound both
horns together to check for
Figure 10-56—Matched Horn Set
proper blend of tone. If adjustment
does not provide a satisfactory
tone, horn contacts are pitted,
making horn r e p l a c e m e n t
necessary.
5. With horns reinstalled on car,
connect a volt-meter b e t w e e n
each horn terminal and ground to
check voltage while both horns
are blowing. This should be be-
tween 7 and 11 volts.
10-47 DIRECTION
SIGNAL LAMPS
AND SWITCH
a. Direction Signal Lamps
and Indicators
The front direction signal light
is produced by the 32 CP fila-
ment in the dual purpose bulb
mounted in the front parking
lamp. The rear direction signal
light is produced by the 32 CP
filament in the bulb of the rear
lamp assembly. This filament
also serves as a stoplight.
When the ignition switch is turned
on and the direction signal switch
is manually operated to indicate
a turn, the front and rear signal
lights flash on and off on the side
of car for which a turn is in-
dicated. The flashing of signal
lights is caused by a flasher
which is c o n n e c t e d into the
proper signal circuit by contacts
made in the direction switch when
switch is set for a turn.
When the direction signal lights
are flashing, a signal indicator