The second method is to put the suspect component into a freezer
long enough for any water to freeze. Reinstall the part into the car
and check for the reoccurrence of the incident. If it occurs, repair
or replace the component.
SGI844
WATER INTRUSION
NLGI0005S0205
The incident may occur only during high humidity or in rainy/snowy
weather. In such cases the incident could be caused by water
intrusion on an electrical part. This can be simulated by soaking the
car or running it through a car wash.
Do not spray water directly on any electrical components.
SGI845
ELECTRICAL LOAD
NLGI0005S0206
The incident may be electrical load sensitive. Perform diagnoses
with all accessories (including A/C, rear window defogger, radio,
fog lamps) turned on.
COLD OR HOT START UP
NLGI0005S0207
On some occasions an electrical incident may occur only when the
car is started cold. Or it may occur when the car is restarted hot
shortly after being turned off. In these cases you may have to keep
the car overnight to make a proper diagnoses.
Circuit Inspection
NLGI0005S03
INTRODUCTION
NLGI0005S0301
In general, testing electrical circuits is an easy task if it is
approached in a logical and organized method. Before beginning
it is important to have all available information on the system to be
tested. Also, get a thorough understanding of system operation.
Then you will be able to use the appropriate equipment and follow
the correct test procedure.
You may have to simulate vehicle vibrations while testing electrical
components. Gently shake the wiring harness or electrical com-
ponent to do this.
OPEN
A circuit is open when there is no continuity through a section of
the circuit.
SHORT
There are two types of shorts.
I
SHORT CIRCUIT
When a circuit contacts another circuit
and causes the normal resistance to
change.
I
SHORT TO GROUND
When a circuit contacts a ground source
and grounds the circuit.
HOW TO PERFORM EFFICIENT DIAGNOSES FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont’d)
GI-24