ENGINE-ELECTRICAL 6Y-10
circuit. Make absolutely certain all connections in
the circuit are secure.
5.
Do not short across or ground any of the terminals
on the generator or regulator.
6. Do not attempt to polarize the generator.
7.
Do not disconnect lead at generator without first dis-
connecting battery ground cable.
Trouble in the A.C. charging system will usually be
indicated by one or more of the following conditions:
1.
Faulty indicator lamp or ammeter operation.
2.
An undercharged battery (usually evidenced by slow
cranking speeds).
3.
An overcharged battery (usually evidenced by exces-
sive battery water usage).
4.
Excessive generator noise or vibration.
Described below are a series of on-the-vehicle quick
checks which are designed to assist the service tech-
nician in locating troubles within the various components
of the engine electrical system. Additional checks, ad-
justments and overhaul procedures of these components
are also described in the "Charging Systems—Service
Operations Section" and should be referred to as
necessary.
STATIC CHECKS
Before making any electrical checks, perform the fol-
lowing static checks:
1.
Check for loose fan belt.
2.
Check for defective battery. (Refer to Battery).
3.
Inspect all connections, including the slip-on con-
nectors at the regulator and Delcotron.
NOTE: Do not short field to ground to check if
generator is charging since this will seriously
damage the charging system.
SYSTEM CONDITION TEST
This test is used .to indicate the overall condition of the
charging system (both good and defective) and to isolate
the malfunctioning unit if the system is defective.
NOTE: On Corvette models difficulty may be
encountered -when attempting to make the re-
quired test connections at the voltage regulator.
It is advisable to remove the regulator from its
mounting location to perform the necessary con-
nections at the regulator for the following tests
but make sure unit is grounded.
1.
With ignition off, perform the prescribed Static
Checks outlined in this section. Then set hand brake
and shift transmission
into
neutral.
2.
Connect a voltmeter from junction block relay to
ground at regulator base.
CAUTION: Be sure meter clip does not touch a
resistor or terminal extension under regulator,
3.
Connect a tachometer on engine.
4.
Models equipped with Indicator Lamp: Turn ignition
switch on "ON" position and check indicator lamp.
If lamp fails to glow, perform appropriate tests and
corrections (Indicator Lamp Circuit Tests) before
continuing.
Models equipped with Ammeter: Turn ignition
switch to "ACC" with an accessory on and check
ammeter. If ammeter fails to read discharge, check
ammeter circuit before continuing.
5.
Models equipped with Indicator Lamp: If lamp glows,
start the engine and run' it at 1500 rpm or above.
Check indicator lamp. If lamp fails to go out, per-
form appropriate test and corrections (Indicator
Lamp Circuit Test) before continuing.
Models equipped with Ammeter: If ammeter reads
discharge, start the engine and observe ammeter. If
meter fails to move toward charge (from original
position), perform appropriate test and corrections
(Field Circuit Tests) before continuing.
NOTE: At this point a field circuit has been
established and any other problem will lie in
generator or regulator.
6. Turn on high-beam headlights and heater blower
motor to high speed, run engine at or above 1500
rpm (for a few minutes, if necessary) and read the
voltage on meter.
AIR GAP
ADJUSTING NUT
ONLY
ADJUSTING SCREW
(Turn To Adjust
Voltage Setting)
Fig.
6c—Adjusting Voltage Setting
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 12
ELECTRICAL-BODY AND CHASSIS
CONTENTS
OF
THIS
SECTION
Page
Page
System 12-1
Instruments and Gauges 12-21
Directional Signal 12r40
Windshield Wipers and Washers 12-44
Wiring Diagrams 12-56
Special Tools 12-60
LIGHTING SYSTEM
INDEX
Page
General Description
!2-i
Maintenance and Adjustments
•.................. 12-2
Headlamp Adjustment......................
12-3
Headlamp Panel Travel Adjustment.
12-5
Service Operations.
. . .. 12-5
Front Lighting
12-5
Headlamp
. 12_5
Parking Lamp
12-5
Fender Lamp
. 12_^
Headlamp Panel
12-8
Headlamp Panel Motor
^2-9
Rear Lighting
l2-10
Tail, Stop and Directional Lamps
12-10
Page
Backing Lamps
12-14
License Plate Lamp
12-14
Automatic Transmission Quadrant Lamp
12-14
Seat Separator Console Lamps
. 12-15
Lighting Switch
. . 12-15
Wiper Switch.
12-15
Stoplight Switch
12-15
Dimmer Switch
12-15
Backing Lamp Switches
12-15
Neutral Safety Switches
12-17
Parking Brake Alarm Switch
................. 12-19
Instrument Panel Compartment Lamp/Switch
12-19
Cirgarette Lighter
12-19
GENERAL DESCRIPTION
.
The lighting system includes: the main lighting switch,
stop light, dimmer, and backing lamp switches, head-
lamps, parking lamps, stop, tail and directional lamps,
instrument illumination and indicator lamps, and the
necessary wiring to complete the various circuits. A
fuse panel provides convenient power take offs and fuse
clips for the appropriate circuits (fig. 1).
Chevrolet and Chevelle headlamp installation is all
new in that the headlamps are located in the radiator
support with adjusting screws and springs. Eliminating
the need for having separate headlamp housings. Chev-
rolet and Chevelle headlamp retainers and springs are
interchangeable.
Chevy n headlamp housings are new because of revised
front end styling and Corvette front end lighting is basi-
cally carryover.
Front fender lamps have been added as an option for
Chevrolet models and as standard equipment on Caprice
series.
Camaro models use single headlamps and the Rally
Sport model headlamps are covered by a retractable
section of the grille when lamps are not used. The sec-
tion of the grille covering the headlamps folds back when
lights are required; the headlamps are stationary. The
covering is retracted by a small electric motor mounted
to the headlamp housing. The headlamps are automat-
ically uncovered when the headlight switch is pulled "ON"
for illumination. If at any time the electrical circuit
becomes inoperative, the lamps can be uncovered manu-
ally. The ignition switch must be
"ON"
in order to close
the headlamp doors.
Parking lamp for Chevelle and Chevrolet models are
new due to revised front end sheet metal and bumper
styling. Parking lamps are located in the bumper on
Chevrolet, Chevelle and Chevy n models
Camaro parking lamps are located in the radiator
grille except for the Rally Sport models on which the
parking lamps are in the valance panel. For styling
reasons, the lens is white and an amber glass bulb is
used. All Camaro parking lamps require a separate
ground wire to assure a good ground contact because of
the plastic grille and painted contact surfaces.
The Chevrolet tail, stop, and directional lamps are in
one housing with a three section lens design on Impala
and Caprice sedans. The center lens for Impala series
is the back-up lamp. The center lens on the Caprice is
a tail lamp with the back-up lamps being located in the
rear bumper. Chevrolet station wagons have three indi-
vidual housings with three lenses, the center lamp being
the back-up. Biscayne and Bel-Air sedans have a single
housing and lens for tail, stop, and directional lamp with
a similarly constructed back-up lamp inboard and adja-
cent to it.
Chevelle tail, stop, and directional lamps are a single
lens design that follows through with the rear fender
styling. The back-up lamp is located in r.ear bumper.
Camaro models except Rally Sport have tail lamps
with integral back-up lamps mounted inboard of the rear
fenders between the trunk opening and bumper. The
Rally Sport model has dual tail lamps in the rear housing
and valance mounted back-up lamps.
Corvette, Chevy n, and Corvair tail and directional
signal lights are carryover. The Corvette has new back-
up lamps center mounted above the license plate opening.
CHEVROLET CHASSIS SERVICE
ELECTRICAL-BODY AND CHASSIS 12-21
2.
Remove ash tray, retainer attaching screws and
retainer.
3.
Remove Air Conditioning distributor
duct'
retaining
screws and duct.
4.
Remove heater and/or Air Conditioning control panel
assembly retaining screws and push panel assembly
from console.
NOTE:
If interference between control panel
and radio is encountered, loosen radio retaining
nuts.
5. Remove radio control knobs, bezels and retaining
nuts.
6. Disconnect radio wiring harness and antenna lead-in.
7. Remove radio rear brace attaching screw and re-
move ra(Jio from vehicle.
8. Remove ignition switch bezel nut using Tool J-7607
and push switch rearward.
9. Disconnect cigarette wiring connector.
10.
Remove cigarette lighter retainer and lighter as-
sembly from console.
11.
To install, reverse removal procedure.
Fig.
35 - Cigarette Lighter — Chevelle
CHEVROLET INSTRUMENTS AND GAUGES
INDEX
Page
General Description 12-21
Service Operations 12-22
Instrument Cluster........................ 12-22
Instrument Cluster Lamps 12-22
Printed Circuit .
* •
12-22
Speedometer 12-22
Speedometer Cable 12-23
Fuel Gauge 12-23
Page
Clock 12-24
Tachometer 12-24
Ammeter . . 12-24
Temperature Gauge 12-24
Oil Pressure Gauge 12-24
Oil Pressure Indicator 12-24
Generator Indicator 12-26
Temperature Indicator 12-26
GENERAL DESCRIPTION
The standard instrument cluster on all models contains
seven circular housings consisting of: a speedometer;
fuel gauge; oil pressure, generator and temperature indi-
cators; right and left directional signal indicators; brake
warning and high beam indicators; and includes a clock
on deluxe models. An optionally available instrument
cluster provides special instrumentation which includes
in addition to the speedometer and clock: a tachometer;
fuel, oil pressure, ammeter and engine temperature
gauges; which replace the standard fuel gauge and indi-
cator lights. The brake warning indicator is relocated
to the tachometer dial face and the high beam and direc-
tional indicators are positioned in the speedometer dial
face.
Instrument cluster removal is recommended before at-
tempting to service the printed circuit and gauges even
though some units may be accessible from behind the
cluster. Limited working space under the instrument
panel increases the possibility of electrical malfunctions
due to poor connections, and damaged or improperly in-
stalled printed circuit. The printed circuit is service-
able but not repairable and requires complete
replacement.
The brake warning light serves a dual purpose. It
functions as an indicator when the parking brake is ap-
plied and also warns if a malfunction (loss of hydraulic
pressure) should occur in the brake system. The two
separate switches, which provide the signal to operate the
indicator, are located at the parking brake support and in
the hydraulic brake line at the master cylinder. Service
of the brake pressure, differential switch unit at the
master cylinder is described in Section 5 of this manual.
All indicator and cluster illumihating lamps may be
replaced without removing the cluster from the vehicle.
The bulbs are installed in plastic holders which lock into
the cluster housing and make contact with the printed
circuit. An instrument lamp is used to illuminate the
ignition switch. A special fibre optic lucite wiring
transmits light from the lamp to the switch.
Regular maintenance is not required on the instrument
cluster or its components other than maintaining clean,
tight electrical connections, replacing defective parts and
keeping the speedometer cable properly lubricated.
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY
AND
CHASSIS
12-26
•
Low oil
pressure
• High engine temperature
• Defective wiring
or
switch
connector from sender
in block above starter
on
and
at
left front
of
distributor
on V-8
Sending Unit Replacement
1.
Disconnect wiring harness
unit terminal (located
L-6 engines
engines).
2.
Remove sender unit using Tool J-21757
or 12
point
socket, replace with
new
unit
and
check operation.
GENERATOR INDICATOR
1.
Ignition
on,
Engine
not
Running
and
Telltale Light
Off.
• Indicator bulb burned out, replace bulb.
• Open circuit
or
loose connection
in the
telltale
light circuit.
2.
telltale Light Stays
on
after Engine
is
Started.
If indicator light does
not go out at
engine idle
speed, refer
to
Charging Systems under Engine
Electrical, Section
6Y.
TEMPERATURE (COOLING SYSTEM) INDICATOR
The temperature indicator circuit consists
of two re-
motely located units, indicator gauge
and
engine sender
unit.
The
indicator gauge, located
in the
instrument
panel, consists
of a
red light which will indicate
an
over-
heated engine condition.
Engine Sender Unit Replacement
1.
Drain engine cooling system
to a
level below unit.
2.
Remove sender unit (located
in the
inlet manifold
near water pump housing
on V-8
engines and
in the
cylinder head near
an
exhaust port
oh L-6
engines)
and replace with new unit.
3.
Refill cooling system
and
check operation
of
unit.
CHEVELLE INSTRUMENTS AND GAUGES
INDEX
Page
General Description
* *
i2-26
Service Operations
12-26
Instrument Panel
12-26
Instrument Cluster.
12-26
Fuel Gauge and/or Ammeter
12-27
Clock,
i 12-27
Speedometer
12-27
Page
Speedometer Cable
.
. 12-27
Temperature Gauge
12-29
Oil Pressure Gauge
12-29
Indicator Lights.
. 12-29
Oil Pressure Indicator
12-29
Generator Indicator
. . 12-29
• Temperature Indicator
12-29
GENERAL DESCRIPTION
The Chevelle instrument cluster assembly consists
of:
a speedometer;
a
fuel gauge;
a
generator,
an
engine
tem-
perature and an
oil
pressure indicator lamp, and includes
a clock
on
deluxe models.
On
super sport models,
am-
meter, coolant temperature
and oil
pressure gauges
re-
place
the
appropriate indicator lights. Except
for the
speedometer,
all of the
indicator lamps, instruments
and
gauges
of
these clusters may
be
serviced without remov-
ing
the
instrument cluster assembly from
the
vehicle.
In addition
to the
instrument indicator lamps,
a
brake
warning lamp
is
included
in the
cluster
as
standard
equipment.
The
indicator
is
connected
to the
parking
brake
and
brake pressure differential switches
and
serves
a
dual function.
It
lights when the parking brake
is applied
and
also when
the
brake pedal
is
applied,
if a
malfunction should occur
in the
brake system
due to a
loss
of
hydraulic pressure. Servicing
of the
hydraulic
pressure differential switch
is
covered
in
Section
5 of
this manual.
Regular maintenance
is not
required on the instrument
cjLuster
or its
components other than maintaining dean
and tight electrical connections, replacing defective parts
and keeping
the
speedometer cable properly lubricated.
SERVICE OPERATIONS
INSTRUMENT PANEL ASSEMBLY
INSTRUMENT CLUSTER (Figs.
41
thru
44)
Removal
1.
Disconnect battery ground cable.
2.
Remove steering coupling bolt and disconnect steer-
ing shaft from coupling.
3.
Loosen mast jacket lower clamp.
4.
Remove
air
conditioning center distributor duct
(if
so equipped).
5. Remove radio rear support bracket screw.
6. Remove mast jacket upper support clamp and retain-
ing bolts from lower support (refer
to
Section
9,
Steering).
CAUTION: Cover mast jacket
and
parl
brake handle with
a
suitable material
to
prevc
scratching.
7.
Disconnect speedometer cable
at
rear
of
cluster
housing
and
speed warning control knob
at
panel
(if
so equipped).
8. Remove instrument panel retaining screws (nine
upper and five lower).
.
9. Working under the console remove four lower retain-
ing screws from instrument cluster housing.
10.
Pull instrument panel assembly from console and
lay
forward on mast jacket.
11.
Disconnect wiring harness, cluster lamps and wiring
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY
AND
CHASSIS
12-31
CHEVY II INSTRUMENTS AND GAUGES
INDEX
Page
Page
General Description -.....
12-31
Service Operations.
12-31
Instrument Panel
. 12-31
Instrument Cluster
12-31
Fuel Gauge
12-32
12-32
Clock,
Speedometer
12-34
Speedometer Catte
12-34
Indicator Lights
12-34
Oil Pressure Indicator
12-34
Generator Indicator
12-34
Temperature Indicator
12-34
GENERAL DESCRIPTION
The Chevy
n
instrument cluster assembly consists
of:
a speedometer;
a
fuel gauge;
a
generator, temperature
and
oil
pressure indicator lamps, and includes
a
clock
on
deluxe models. Except
for the
speedometer,
all of the
cluster lamps, instruments and gauges
of
the cluster
may
be serviced without removing
the
instrument cluster
as-
sembly from
the
console.
In addition
to the
instrument indicator lamps,
a
brake
warning lamp
is
included
in the
cluster
as
standard
equipment.
The
indicator
is
connected
to
thfc parking
brake and brake pressure differential switches andserves
a dual function.
It
lights when
the
parking brake
is ap-
plied
and
also when
the
brake pedal
is
applied,
if a mal-
function should occur
in the
brake system
due to a
loss
of
hydraulic pressure. Servicing
of the
hydraulic pressure
differential switch
is
covered
in
Section
5 of
this manaul.
Regular maintenance
is not
required on
the
instrument
cluster
or its
components other than r^Mfitftl^i^g clean
and tight electrical connections, replacing defective parts
and keeping
the
speedometer cable properly lubricated.
SERVICE OPERATIONS
INSTRUMENT PANEL
INSTRUMENT CLUSTER
Removal
and
Installation {Figs.
45
thru
48)
1.
Disconnect battery ground cable.
2.
Remove mast jacket upper support clamp (refer
to
Steering, Section
9, for
complete procedure
on low-
ering jacket) and lower steering column.
NOTE:
Apply protective material
to the
mast
jacket
to
prevent damage
to the
painted surfaces.
3.
Disconnect retaining collar securing speedometer
cable
to
speedometer head.
4.
Remove screws retaining cluster
to
console.
5. Pull cluster forward
of
console opening and discon-
nect
all
wiring
and
lamp connections. Remove
cluster from vehicle.
CAUTION:
Do not
pull cluster outward further
than slack
in
wiring harness will allow, other-
Fig.
45-
Instrument Cluster Installation
—
Chevy
II
Fig.
46 -
Speed Warning Device
CHEVtOtET CHASSIS SERVICE MANUAL