E-3.
TM 5-3805-262-20
APPENDIX E
HYDRAULIC, PNEUMATIC, AND ELECTRICAL DIAGRAMS
Section I. INTRODUCTION
E-1. GENERAL
This appendix contains an electrical schematic diagram, electrical system wiring di-
agram, pneumatic diagram, and hydraulic diagrams.
Also included in this appendix is
a description of how to use the electrical schematic diagram as an aid to trouble-
shooting (section II).
E-2. DIAGRAMS
Foldout diagrams FO-1 through FO-11 are located at the back of this manual.
Section II. HOW TO USE ELECTRICAL SCHEMATIC AS AN AID TO TROUBLESHOOTING
a. Figure FO-3, your Electrical Diagram, is designed to help you understand the
electrical circuits associated with this vehicle.
It is generally referred to as a
“schematic” and uses “symbols” to represent real components.
It is not drawn to
scale (as in a blueprint) nor does the location of the symbols represent actual lo-
cation of components in the vehicle.
It is a simple “picture” of how the circuits
and components are connected together.
b. To quickly find a malfunction or trouble in the electrical system and repair
it requires an understanding of how the system operates and a method for checking it
out .
“Troubleshooting” provides the “method” for check out procedures and your
technical manual (Troubleshooting tables and schematics) provides the “operating
principles”.
E-4. TROUBLESHOOTING
Troubleshooting is the systematic (step-by-step) isolation of a malfunction or trou-
ble to the faulty component, harness connector/wire. It is a guide that helps de-
velop a routine or “way” of finding troubles in any electrical system or circuit.
As you become more familiar with this vehicle and gain experience, you will find
ways to shorten these procedures and decrease down time.
BEFORE you attempt to make
any repairs or checks, do the following:
a. Find out how the system works under normal conditions and how to operate it.
b. Make sure the malfunction or trouble reported to you “really” exists.
(“Dead
batteries” could end up as a “failure to start” because-of a faulty neutral start
switch or the transmission shift lever not fully engaged in park or neutral.)
Try
to duplicate the trouble so you can be sure you're on the right track.
E-1
