Buick LeSabre 1965 Service Manual page 641

ELECTRICAL SYSTEMS ACCESSORY SWITCHES 1 0 - 7 1
by holding one end vertically in
each hand and turning cable slow-
ly; if cable is kinked, the loop
will "flop". R e p l a c e a cable
which has kinks or bent tips.
3. Before installing a new inner
cable, work AC spec. 640 speed-
ometer cable lubricant into the
cable thoroughly, then wipe off
all excess lubricant. Since the
speedometer casing has a Delrin
(plastic) liner, this lubricant is
used as a rust preventive only.
4. If noise is still present, in-
stall a new speedometer cable
assembly.
5. If this does not correct noise,
have speedometer head checked
by a UMS Service Station.
d. Trouble-Shooting
Speedometer Safety-Buzzer
The safety-buzzer consists of a
buzzer which may be adjusted by
the driver to sound at any speed
between 30 and 90 MPH by turn-
ing a knob at the bottom of the
speedometer face. The speed at
which the safety-buzzer is set is
indicated by a special pointer with
a yellow ball in the speedometer
face. When the pointer is turned
to the end of its travel (90 MPH),
the buzzer turns off.
The safety-buzzer electrical cir-
cuit starts at a 7.5 ampere fuse
marked "BK & BZ" located on
the fuse block. Since this fuse
also protects the parking brake
warning light, a functioning warn-
ing light indicates that this fuse
is OK. This circuit is "hot"
whenever the ignition switch is
turned on. From the fuse, a dark
green wire carries the current to
a buzzer mounted on a bracket lo-
cated under right side of instru-
ment cluster. A f t e r passing
through the buzzer contacts, a
very small amount of current
goes through a resistor to ground
and the rest of the current passes
through a blue wire to the con-
nector plug located on the speed-
ometer case.
In the speedometer, current is
conducted from the s e p a r a t e
buzzer connector through a wire
to an insulated pin in the lower
end of the safety-buzzer pointer.
As the speedometer pointer moves
up to coincide with the safety-
buzzer pointer, a light grounding
hair spring on the lower end of
the speedometer pointer makes
contact with the "hot" insulated
pin on the safety-buzzer pointer.
This grounds the circuit, causing
the buzzer to buzz. If the car
speed is increased beyond the
safety-buzzer setting, the insu-
lated pin on the safety-buzzer
p o i n t e r "picks-up" the hair
spring as the speedometer pointer
passes under t h e safety-buzzer
pointer and the light grounding
hair spring winds-up slightly.
1- Buzzer Will Not Operate Or
Operates Intermittently.
(a) Turn ignition switch on.
(b) To check buzzer, stick a prod
in terminal at buzzer connector
with the blue wire and run jumper
to ground. If buzzer now oper-
ates, circuit is OK through buzzer
and trouble must be in wire to
speedometer or in speedometer.
To check buzzer circuit up to
speedometer, stick prod in buzzer
connector at speedometer and run
jumper to ground. If buzzer oper-
ates, circuit is OK to speed-
ometer so trouble must be in
speedometer.
(c) If buzzer did not operate when
buzzer connector was grounded
(in Step b), trouble may be in
buzzer circuit. Check "BK &BZ"
fuse on fuse block and replace
7.5 ampere fuse if necessary.
NOTE: Since this fuse also pro-
tects the parking brake warning
light, a functioning warning light
indicates that this fuse is OK.
(d) Check buzzer circuit wiring
connectors at fuse block and at
buzzer.
(e) Next eliminate b u z z e r as
source of trouble by unplugging
connector at buzzer. Then plug
a known good buzzer onto the
connector and ground buzzer.
2. Buzzer Operates Continuously
(a) Check blue wire from buzzer
to speedometer for ground.
(b) Remove buzzer connector at
speedometer. If buzzer s t o p s ,
circuit is grounded inside speed-
ometer and speedometer must be
removed for repair. If buzzer
still operates, however, buzzer
unit is defective and must be
replaced.
3. Speedometer Defective
A defective speedometer assem-
bly must be sent to the nearest
UMS Service Station for repairs.
1 0 - 5 3 ACCESSORY
SWITCHES O N
CONTROL PANEL
The a c c e s s o r y switches are
mounted on a control panel loca-
ted above the radio trim plate.
These switches operate the power
rear window on estate wagons,
the power top on convertibles,
the power antenna and the cour-
tesy light, when so equipped. See
Figure 10-87.
To remove one of these switches,
it is necessary to first remove
the control panel.