GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 127
The normal automotive circuit differs from
this simple example in two ways.
First, instead of having a return wire from the bulb to the battery, the current
travels through the frame of the vehicle. Since the negative (—) battery cable is
attached to the frame (made of electrically conductive metal), the frame of the
vehicle can serve as a ground wire to complete the circuit. Secondly, mo\
st
automotive circuits contain multiple components which receive power from a
single circuit. This lessens the amount of wire needed to power components on
the vehicle.
HOW DOES ELECTRICITY WORK: THE WATER ANALOGY
Electricity is the flow of electrons - t he subatomic particles that constitute the
outer shell of an atom. Elec trons spin in an orbit around the center core of an
atom. The center core is comprised of protons (positive charge) and neutrons
(neutral charge). Electrons have a negativ e charge and balance out the positive
charge of the protons. When an outside forc e causes the number of electrons to
unbalance the charge of the protons, the electrons will split off the atom and
look for another atom to balance out. If th is imbalance is kept up, electrons will
continue to move and an elec trical flow will exist.
Many people have been taught electrical th eory using an analogy with water. In
a comparison with water flowing through a pipe, the electrons would be the
water and the wire is the pipe.
The flow of electricity can be measur ed much like the flow of water through a
pipe. The unit of measur ement used is amperes, frequently abbreviated as
amps (a). You can compare amperage to th e volume of water flowing through a
pipe. When connected to a circuit, an ammeter will measure the actual amount
of current flowing through the circuit. W hen relatively few electrons flow through
a circuit, the amperage is low. When many electrons flow, the amperage is high.
Water pressure is measured in units su ch as pounds per square inch (psi); The
electrical pressure is m easured in units called volts (v). When a voltmeter is
connected to a circuit, it is meas uring the electrical pressure.
The actual flow of electricity depends not only on voltage and amperage, but
also on the resistance of the circuit. T he higher the resistance, the higher the
force necessary to push the current through the circuit. The standard unit for
measuring resistance is an ohm. Resistance in a circuit varies depending on the
amount and type of components used in t he circuit. The main factors which
determine resistance are:
• Material - some materials have more resistance than others. Those with
high resistance are said to be insulato rs. Rubber materials (or rubber-like
plastics) are some of the most common insulators used in vehicles as
they have a very high resistance to electricity. Very low resistance
materials are said to be conductors. Copper wire is among the best
conductors. Silver is actually a super ior conductor to copper and is used
in some relay contacts, but its hi gh cost prohibits its use as common
wiring. Most automotive wir ing is made of copper.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 131
•
Circuit Breaker - a circuit breaker is basically a self-repairing fuse. It will
open the circuit in the same fashio n as a fuse, but when the surge
subsides, the circuit breaker can be reset and does not need
replacement.
• Fusible Link - a fusible link (fuse link or main link) is a short length of
special, high temperatur e insulated wire that acts as a fuse. When an
excessive electrical current passes th rough a fusible link, the thin gauge
wire inside the link melt s, creating an intentional open to protect the
circuit. To repair the circuit, the link must be replaced. Some newer type
fusible links are housed in plug-in modules, which are simply replaced
like a fuse, while older type fusible lin ks must be cut and spliced if they
melt. Since this link is very early in the electrical path, it's the first place to
look if nothing on the vehicle works, yet the battery seems to be charged
and is properly connected.
CAUTION - Always replace fuses, circ uit breakers and fusible links with
identically rated component s. Under no circumstances should a component of
higher or lower amperage rating be substituted.
SWITCHES & RELAYS
Switches are used in electrical circuits to control the passage of current. The
most common use is to open and close circuits between the battery and the
various electric devices in the system. Switches are rated according to the
amount of amperage they c an handle. If a sufficient amperage rated switch is
not used in a circuit, the switch could overload and cause damage.
Fig. 2: The underhood fuse and relay panel usually contains fuses, relays,
flashers and fusible links
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 132
Some electrical components which require
a large amount of current to operate
use a special switch called a relay. Sinc e these circuits carry a large amount of
current, the thickness of the wire in the ci rcuit is also greater. If this large wire
were connected from the load to the c ontrol switch, the switch would have to
carry the high amperage load and the fair ing or dash would be twice as large to
accommodate the increased size of t he wiring harness. To prevent these
problems, a relay is used.
Relays are composed of a coil and a se t of contacts. When the coil has a
current passed though it, a magnetic fiel d is formed and this field causes the
contacts to move together, completing the circuit. Most relays are normally
open, preventing current from passing thr ough the circuit, but they can take any
electrical form depending on th e job they are intended to do. Relays can be
considered "remote control switches." They allow a smaller current to operate
devices that require higher amperages. W hen a small current operates the coil,
a larger current is allo wed to pass by the contacts. Some common circuits
which may use relays are the horn, headlight s, starter, electric fuel pump and
other high draw circuits.
Fig. 3: Relays are composed of a coil and a switch. These two components are
linked together so that w hen one operates, the other operat es at the same time.
The large wires in the circuit are connect ed from the battery to one side of the
relay switch (B+) and from the opposite side of the re lay switch to the load
(component). Smaller wires are connected from the relay coil to the control
switch for the circuit and from the opposite side of the relay coil to ground
LOAD
Every electrical circuit must include a "load" (something to use the electricity
coming from the source). Without this l oad, the battery would attempt to deliver
its entire power supply from one pole to another. This is called a "short circuit."
All this electricity would take a short cut to ground and cause a great amount of
damage to other components in the circui t by developing a tremendous amount
of heat. This condition could develop suffici ent heat to melt the insulation on all
the surrounding wires and reduce a multiple wire cable to a lump of plastic and
copper.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 133
WIRING & HARNESSES
The average vehicle contains meters
and meters of wiring, with hundreds of
individual connections. To protect the many wires from damage and to keep
them from becoming a confusing tangl e, they are organized into bundles,
enclosed in plastic or taped together and called wiring harnesses. Different
harnesses serve different parts of the vehi cle. Individual wires are color coded
to help trace them through a harness wher e sections are hidden from view.
Automotive wiring or circuit conductors can be either single strand wire, multi-
strand wire or printed circui try. Single strand wire has a solid metal core and is
usually used inside such components as alternators, motors, relays and other
devices. Multi-strand wire has a core made of many small strands of wire
twisted together into a single conductor. Most of the wiring in an automotive
electrical system is made up of multi-strand wire, either as a single conductor or
grouped together in a harness. All wiring is color coded on the insulator, either
as a solid color or as a colored wire wit h an identification stripe. A printed circuit
is a thin film of copper or other conducto r that is printed on an insulator backing.
Occasionally, a printed circuit is sandwic hed between two sheets of plastic for
more protection and flexibility. A comp lete printed circuit, consisting of
conductors, insulating material and connec tors for lamps or other components
is called a printed circuit board. Printed ci rcuitry is used in place of individual
wires or harnesses in places where space is limit ed, such as behind instrument
panels.
Since automotive electrical systems are very sensitive to changes in resistance,
the selection of properly sized wires is critical when systems are repaired. A
loose or corroded connection or a replacem ent wire that is too small for the
circuit will add extra resistance and an addi tional voltage drop to the circuit.
The wire gauge number is an expression of the cross-section area of the
conductor. Vehicles from countries that use the metric system will typically
describe the wire size as its cross-secti onal area in square millimeters. In this
method, the larger the wire, the gr eater the number. Another common system
for expressing wire size is the Americ an Wire Gauge (AWG) system. As gauge
number increases, area decreases and the wire becomes smaller. An 18 gauge
wire is smaller than a 4 gauge wire. A wire with a higher gauge number will
carry less current than a wire with a lower gauge number. Gauge wire size
refers to the size of the strands of the conductor, not the size of the complete
wire with insulator. It is possi ble, therefore, to have two wires of the same gauge
with different diameters because one may hav e thicker insulation than the other.
It is essential to understand how a circuit works before trying to figure out why it
doesn't. An electrical schematic shows the electrical current paths when a
circuit is operating proper ly. Schematics break the enti re electrical system down
into individual circuits. In a schematic, usually no attempt is made to represent
wiring and components as they physically appear on the vehicle; switches and
other components are shown as simply as possible. Face views of harness
connectors show the cavity or terminal lo cations in all multi-pin connectors to
help locate test points.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 151
ARMING THE SYSTEM
1. Turn the ignition key to the LO CK position and remove the key.
2. On vehicles with a passenger side ai r bag, reconnect the yellow two-way
connector assembly located near the yellow 24-way DERM harness
connector. Install the glov e box door assembly.
3. Connect the yellow two-way connector assembly at the base of the
steering column.
Always be sure to reinstall the Connec tor Position Assurance (CPA) device.
4. Install the left side trim panel and rein stall the fuse in the fuse block.
5. Turn the ignition key to the RUN posit ion and verify that the warning lamp
flashes seven to nine times and then turn s OFF. If it does not operate as
described, have the system repair ed by a qualified technician.
HEATING AND AIR CONDITIONING
BLOWER MOTOR
REMOVAL & INSTALLATION 1. Disconnect the negative battery cable. If necessary, remove the diagonal
fender brace at the right rear corner of the engine compartment to gain
access to the blower motor.
2. Disconnect the electrical wiring fr om the blower motor. If equipped with
air conditioning, remove the blower relay and bracket as an assembly
and swing them aside.
3. Remove the blower motor cooling tube.
4. Remove the blower mo tor retaining screws.
5. Remove the blower motor and fan as an assembly from the case.
To install: 6. Position the blower motor into pl ace and install the retaining screws.
7. Install the blower motor cooling tube.
8. Connect all the electrical connections.
9. Connect the negative battery cable.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 182
ANTENNA
REMOVAL & INSTALLATION
Placement of tape on the right inner door edge will help prevent scratches
during the antenna removal an
d installation procedure.
1. Disconnect the negative battery terminal.
2. Remove the right side lower in strument panel sound insulator and
disconnect the antenna connection from the radio.
3. Raise and safely support the vehicle.
4. Disconnect the instrument panel harness from the radio.
5. Disconnect the power antenna lead, if equipped.
6. Disconnect the power antenna wire from the relay, if equipped.
7. Remove the right fender wheelhouse.
8. Loosen the fender-to-body attaching bolts and block the fender out.
9. Remove the antenna bezel and nut.
10. Remove the antenna assembly mounting screws.
11. Remove the grommet from the bul khead and pull the harness from the
vehicle interior.
12. Remove the antenna assembly from the vehicle.
In some cases, if the vehicle is equipped with a power antenna, it may be
repaired. Seek a profe ssional radio shop for pr oper repair of the antenna
assembly.
To install: 13. Install the antenna assembly into the vehicle.
14. Install the grommet and the harne ss into the vehicle interior.
15. Install the antenna assembly mounting screws.
16. Install the antenna bezel and nut.
17. Remove the fender block, tighten the fender-to-body attaching bolts.
Ensure any shims for the fender are reinstalled.
18. Install the right fender wheelhouse.
19. Lower the vehicle.
20. Connect the power antenna wire to the relay, if equipped.
21. Connect the power ant enna lead, if equipped.
22. Connect the instrument panel harness to the radio.
23. Connect the antenna connection to the r adio. Install the right side lower
instrument panel sound insulator
24. Connect the negative battery cable.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 224
BUZZERS, RELAYS, AND FLASHERS
The electrical protection dev
ices are located in the convenience center, which is
a swing down unit located under the inst rument panel. All units are serviced by
plug-in replacements.
TURN SIGNAL FLASHER
The turn signal flasher is located inside th e convenience center. In order to gain
access to the turn signal flasher, it ma y be necessary to first remove the under
dash padding.
HAZARD FLASHER
The hazard flasher is located inside the convenience center. In order to gain
access to the turn signal flasher, it ma y be necessary to first remove the under
dash padding.
GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 345
operation is required of it. Thus, little a
llowance for air circulation is required,
and the windings can be built into a very small space.
The starter solenoid is a magnetic dev ice which employs the small current
supplied by the starting switch circuit of the ignition switch. This magnetic action
moves a plunger which mechanically engages the starter and electrically closes
the heavy switch which connects it to t he battery. The starting switch circuit
consists of the starting switch cont ained within the ignition switch, a
transmission neutral safety switch or clutch pedal switch, and the wiring
necessary to connect these with the starter solenoid or relay.
A pinion, which is a small gear, is m ounted to a one-way drive clutch. This
clutch is splined to the starter armature shaft. When the ignition switch is moved
to the start position, the solenoid plunger slides the pinion toward the flywheel
ring gear via a collar and spring. If t he teeth on the pinion and flywheel match
properly, the pinion will engage the flywheel immediately. If the gear teeth butt
one another, the spring will be compressed and will force the gears to mesh as
soon as the starter turns far enough to a llow them to do so. As the solenoid
plunger reaches the end of it s travel, it closes the contacts that connect the
battery and starter and then the engine is cranked.
As soon as the engine star ts, the flywheel ring gear begins turning fast enough
to drive the pinion at an ex tremely high rate of speed. At this point, the one-way
clutch begins allowing the pi nion to spin faster than the starter shaft so that the
starter will not operate at excessive speed. When the i gnition switch is released
from the starter position, the solenoid is de-energized, and a spring contained
within the solenoid assembly pulls the gear out of mesh and interrupts the
current flow to the starter.
Some starters employ a separate relay, mounted away from the starter, to
switch the motor and solenoid current on and off. The relay thus replaces the
solenoid electrical switch, but does not eliminate the need for a solenoid
mounted on the starter used to mechanica lly engage the starter drive gears.
The relay is used to reduce the amount of current the starting switch must carry.
THE CHARGING SYSTEM
The automobile charging system provides electrical power for operation of the
vehicle's ignition and star ting systems and all the electrical accessories. The
battery serves as an electrical surge or storage tank, storing (in chemical form)
the energy originally pr oduced by the engine driven gen erator. The system also
provides a means of regulating alternat or output to protect the battery from
being overcharged and to avoid excess ive voltage to the accessories.
The storage battery is a chemical device in corporating parallel lead plates in a
tank containing a sulfuric acid-water solution. Adjacent plates are slightly
dissimilar, and the chemical reaction of the two dissimilar plates produces
electrical energy when the battery is connected to a load such as the starter
motor. The chemical reaction is reversible, so that when the generator i\
s
producing a voltage (electrical pressure ) greater than that produced by the