Chevrolet 10 Series 1968, Руководство по обслуживанию

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SECTION 12
ELECTRICAL-BODY AND CHASSIS
CO N TEN TS OF THIS SECTIO N
Page
Lighting S y s te m .......................................................................... 12-1
Instruments and Gauges .......................................................... 12-12
Directional S i g n a l s ............................................................. ...... 12-23
Windshield W ipers and W a s h e r s ............................................. 12-27
W iring D ia g r a m s ................................................................ ...... 12-32
LIGHTING SYSTEM
INDEX
Page
General Description .......................................................... ...... 12-1
Maintenance and Adjustm ents............................................. ...... 12-1
Headlamp A d ju stm en t....................................................... ...... 12-3
Service O p e r a t io n s ............................................................. ...... 12-5
Sealed Beam Unit R ep la cem en t............................................. 12-5
Parking Lamp R eplacem en t............................................. ...... 12-5
R ear L ig h t in g .......................................................................... 12-5
M arker, Clearance and Iden tifica tion ................................... 12-5
Page
Directional Signal L a m p s ................................................ .... 12-5
W iper Switch R e p la c e m e n t............................................. .... 12-5
Light Switch Replacement ............................................. .... 12-5
Stoplamp Switch Replacement ...................................... .... 12-9
Dim mer Switch R e p la c e m e n t............................. . . . . 12-9
Neutral Safety Switch R ep la ce m en t................... ... . . . 12-9
Backing Lamp Switch R ep la ce m en t................................ .... 12-10
GENERAL DESCRIPTION
The lighting system includes the main light switch;
stop light, dimmer and backing lamp switches; head and
parking lamps; stop, tail, side marker, clearance and
identification lamps; instrument illumination, directional
signal and indicator lamps and the necessary wiring to
complete the various circuits.
A bulkhead fuse panel (fig. 1) provides convenient power
taps and fuse clips for the appropriate circuits. The en­
gine wiring harness and forward lamp harness connectors
are bolted to the fuse panel.
All wiring systems not protected by fuses incorporate
a fusible link which provides increased overload protec­
tion. The starting motor circuit is the exception.
Composite wiring diagrams are included at the end of
this section. The standardized color code is common to
all wiring harnesses. The wire covering color designates
a particular circuit usage.
MAINTENANCE AND ADJUSTMENTS
Maintenance of the lighting units and wiring system
consists of an occasional check to see that all wiring
connections are tight and clean, that the lighting units are
tightly mounted to provide good ground and that the head­
lamps are properly adjusted. Loose or corroded con­
nections may cause a discharged battery, difficult start­
ing, dim lights, and possible damage to generator and
regulator. Wire harnesses must be replaced if insula­
tion becomes burned, cracked, or deteriorated. When­
ever it is necessary to splice a wire or repair one that is
broken, always use solder to bond the splice. Always
use rosin flux solder on electrical connections. Use in­
sulating tape to cover all splices or bare wires.
When replacing wires, it is important that the correct
size be used. Never replace a wire with one of a smaller
size. Fusible links in the Chevrolet wiring are four
gauge sizes smaller than the cable it is designed to pro­
tect. The links are marked on the insulation with wire
gauge size because of the heavy insulation which makes
the link appear a heavier gauge than it actually is.
Each harness and wire must be held securely in place
by clips or other holding devices to prevent chafing or
wearing away the insulation due to vibration.
By referring to the wiring diagrams, circuits may be
tested for continuous circuit or shorts with a conventional
test lamp or low reading volt meter.
CHEVROLET TRUCK SERVICE MANUAL