burned fuses, or corroded battery terminals, a technical
manual may not be required; however, for more
complex, electrical systems, it is a necessity. Use
EXTREME CAUTION when working around any
electrical system on any CESE. Crossing wires or
flashing wires to ground-to check for current may all
lead to major damage, costly repairs, or personnel injury.
When you troubleshoot any system, have a set plan
to approach the problem. Keep it simple; eliminate easy
items, such as a dead battery, burned out light bulbs,
blown fuses, and so forth. Once the simple fixes are out
of the way, use your own set plan to solve the problem.
One plan that may be of help to you is the following:
Know the machine and find and read the
technical manual to understand the problem.
List all the possibilities of the fault.
When possible, speak to the operator and find
out how the unit malfunctioned in a working
Operate and inspect the machine yourself.
Systematically test individual circuits until the
problem is found.
Test your findings.
7. Repair CESE and return it to service.
As an afterthought, once a unit of CESE is repaired
and returned to dispatch, discuss your findings with
other CMs in the shop. Do not play, Ive Got a Secret
with repair information.
Before proceeding with any electrical tests on
automotive or construction equipment, check the power
source (battery) and its connections first. A dead or poorly
grounded battery may not light lights, work solenoids, or
run motors. On the other hand, a poorly grounded battery
may work many of the vehicle components, but not certain
electronic circuits. Remember to check the battery and its
connections first; for the remainder of this chapter, before
any troubleshooting procedures are explained, it will be
assumed that you have done so.
The most common problem in headlight systems is
burned out light bulbs. This may be eliminated simply
by replacing the bulbs. If the head lamp still does not
work, remove the lamp from the socket and check the
leads on the multiwire connector to the lamp with a
12/24 volt test lamp or a volt/ohmmeter (multimeter)
(fig. 4-43). Make sure the headlight switch is turned on.
Figure 4-43.-Troubleshooting headlight wiring (typical military system).