CHAPTER 4. CRANE HYDRAULIC AND ELECTRICAL TROUBLE SHOOTING

TM 5-5420-279-23

CHAPTER 4

Section I. CRANE TROUBLE SHOOTING

4-1

INTRODUCTION

a. Trouble shooting flow charts are provided to guide the Unit Maintenance personnel through to

a procedure for rectifying specific faults.

b. This section is to be used to recognize, diagnose and rectify faults that may occur with the

DSB crane.

4-2

CRANE ELECTRICAL SYSTEM OVERVIEW

a. General Description - An electrical system provides power to switches and solenoids which

when activated allow the operator to control the function of the crane and launcher components.

b. Electrical power is supplied from the host vehicle via the interface enclosure. Harnesses

connect junction boxes, switches and solenoids in the electrical system. Junction boxes redirect

electrical supplies to specific sub-systems.

c. Limit switches and indicators are fitted in the circuit to provide a signal, a visual indication at

the control panel, of the state of a component.

d. Solenoid Valves when activated electrically will allow or stop the flow of hydraulic fluid in the

hydraulic circuits.

4-3

CRANE ELECTRICAL AND HYDRAULIC SCHEMATIC DRAWINGS

a. A set of drawings showing the electrical and hydraulic systems, in detail, are shown in

Appendix J. Appendix J also provides a quick reference guide to the location of the main

electrical components of the crane.

4-4

TROUBLE SHOOTING FLOW CHARTS

a. The trouble-shooting flow charts are designed to assist the Unit Maintenance personnel in

systematically diagnosing a fault and providing a solution for the rectification of that fault.

b. The title of the trouble shooting flow chart is constructed with the TSUM number, subject title.

c. All trouble-shooting flow charts start at the top of a page. The boxes used in the flow charts

depict the following information.

(1)

A circle or rounded rectangle shows the start or end of a flow chart sequence.

(2)

A rectangle or square displays information intended as an instruction or statement.

(3)

A diamond box displays a question or requires the reader to make a decision.

(4)

TSO stands for Trouble Shooting Operator, these can be found in the operator's manual

TM 5-5420-279-10.

(5)

TSUM stands for Trouble Shooting Unit Maintenance.

(6)

A dividing line, where applicable, in a trouble shooting chart details who is responsible

for carrying out the trouble shooting.