Pontiac Fiero 1988 Service Manual page 941

R E P A I R P R O C E D U R E S
E L E C T R I C A L R E P A I R S
This section provides instruction in the fol-
lowing repairs:
— Circuit Protection
— Typical Electrical Repairs
— Splicing Copper Wire
— Splicing Aluminum Wire
— Splicing Twisted/Shielded Cable
— Repairing Connectors (Except Weather
Pack
R
) and
— Repairing Weather Pack" (Environmen-
tal) Connectors
Note:
After any electrical repair is made, always
test the circuit by operating the devices in the
circuit. This confirms not only that the repair is
correct, but also that the cause of the complaint
was correctly identified.
C I R C U I T PROTECTION
All electrical circuits are protected against
excessive loads which might occur because of
shorts or overloads in the wiring system. Such
protection is provided by a fuse, circuit
breaker, or fusible link.
Fuses
The most common method of automotive
wiring circuit protection is the fuse. Whenever
there is an excessive amount of current flow-
ing through a circuit the fusible element will
melt and create an open or incomplete circuit
(see Figure 1). Fuses are a "one time" protec-
tion device and must be replaced each time the
circuit is overloaded.
Auto-fuses are color coded. The standard-
ized color identification and ratings are shown
in Figure 2.
For service replacement, non-color coded
fuses of the same respective current rating can
be used. The current rating of each fuse is
molded into its head.
To determine whether or not an auto-fuse is
blown, remove the suspect fuse and examine
the element in the fuse for a break, (see Figure
1). If the element is broken, replace the fuse
with one of equal current rating.
There are, however, additional specific cir-
cuits with in-line fuses. In-line fuses are
located within the individual wiring harness.
They are usually housed in spring-loaded,
twist-type receptacles.
C U R R E N T
RATING
(AMPERES)
COLOR
3
V I O L E T
5
T A N
7.5
B R O W N
10
R E D
15
B L U E
20
Y E L L O W
25
W H I T E
30
G R E E N
Figure 2 - Fuse Rating And Color
Circuit Breakers
A circuit breaker is a protective device
designed to open the circuit when a current
load is in excess of rated breaker capacity. If
there is a short or other type of overload condi-
tion in the circuit, the excessive current will
open the circuit between the circuit breaker
terminals. The circuit breaker will remain open
until the trouble is found and corrected. The
circuit breaker will close automatically when
the excessive current is removed. The condi-
tion of a circuit breaker may be verified by
removing it from the circuit and checking the
resistance. A good circuit breaker will have
less than 1 ohm resistance between the two ter-
minals.
Figure 1 - Sample Fuses