Chevrolet 70 1969 Series, Shop Manual

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CHASSIS ELECTRICAL A N D INSTRUMENTS 12-12
Figure 14—Replacing Instrument or Tell-Tale Light Bulb
INSTRUMENT A N D TELL-TALE
LIGHTS
The instrument and tell-tale light bulbs are
either wedge base type or single contact, minia­
ture base type. On conventional cab models,
bulbs are installed in pronged bulb sockets which
snap into openings in instrument cluster, gauges,
speedometer and tachometer case. On tilt cab
models, bulbs are installed in plastic holders
which lock into the instrument case and make con­
tact with the printed circuit.
Instrument panel lamp circuit on conventional
cab models is protected by a 5-amp fuse located
on the fuse block. On tilt cab models, instrument
panel lamps are protected by a 14-amp fuse.
B U L B R E P L A C E M E N T
Refer to "Light Bulb Data” at end of this sec­
tion for bulb sizes and trade numbers.
Conventional Cab Models
Pull bulb socket out of instrument cluster,
gauge unit, speedometer case, or tachometer case.
Press bulb in and turn counterclockwise to remove
from socket. Install new bulb in socket, press in
and turn clockwise to lock in place. Press socket
firmly into place in opening in cluster, gauge unit,
speedometer, or tachometer case.
Tilt Cab Models
Turn bulb holder counterclockwise to remove
from case (fig. 18). Pull bulb straight out to remove
from holder. Install new bulb in holder, press in­
ward to lock in place. Insert holder in case with
lugs on holder entering notches in case; then turn
clockwise to lock in place.
DOM E LIGHT
On conventional cab models, dome lamp is
mounted on instrument panel and provides lighting
Figure 15—Dome Light (Tilt Cab Models) ITypical)
to cab interior, glove box, and across the fuse
block. On tilt cab models, the dome light is
mounted at rear of cab above rear window. The
dome light on conventional cab and tilt cab models
is operated by turning the main light switch knob
to extreme counterclockwise position.
B U L B R E P L A C E M E N T
Conventional Cab Models
A tubular type bulb is mounted inside glove
box in front of fuse block and is held in position by
two spring loaded clips. To remove bulb, remove
two screws which attach lens to dash compartment
pillar, then remove lens. Pull bulb forward until
bulb releases from clips. Press new bulb in until
secure in clips.
Tilt Cab Models
Dome light lens is of molded plastic with a
lug molded on edge of lens at center top and bot­
tom. To remove lens, grasp between thumb and
finger at center and squeeze sides together to dis­
engage lugs from assembly. The tubular type bulb
is held in position by two spring-loaded clips (fig.
15). To remove bulb, pull forward until bulb re­
leases from clips. Press new bulb in until secure
in clips, then position lens in assembly and press
in until lugs snap into place.
N O . 7 NO . 6 NO . 1 DO M ELIG HT
Figure
16—Main Light Switch
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SHO P M ANUAL