2
TM 5-3805-296-23-1
FIELD MAINTENANCE
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TROUBLESHOOTING INTRODUCTION
0006
NOTE
Before beginning a troubleshooting procedure, review associated maintenance
procedure(s) and determine the amount of disassembly required to perform a test or
inspection. Disassemble the machine only as far as necessary to test, inspect, or repair
the damaged, broken, or faulty component.
INTRODUCTION
0006
1. This chapter provides information for identifying and correcting malfunctions that may develop during operation
of the Military 621G Scraper.
2. Before performing troubleshooting, read and follow all safety instructions found in the Warning Summary at the
front of this manual.
3. If you are unsure of the location of an item mentioned in troubleshooting, refer to General Information
(WP 0001), or Equipment Description and Data (WP 0002), or to Component Location and Connector End
Views (WP 0012) for referenced connector end views.
4. The Troubleshooting Index (WP 0005) lists the following and refers to the appropriate troubleshooting proce-
dure in this TM;
a. All possible diagnostic codes for the machine.
b. All possible event codes for the machine.
c.
Symptoms of common malfunctions that may occur.
5. The Troubleshooting Index (WP 0005) cannot list all malfunctions that may occur.
6.
Troubleshoot diagnostic codes first, then event codes, then the symptom, unless otherwise directed by trou-
bleshooting. During testing, components and wiring harnesses will be disconnected and may set unrelated
diagnostic codes or event codes.
7. When troubleshooting a malfunction:
a. Locate the symptom in the Troubleshooting Index (WP 0005) that best describes the malfunction.
b. Turn to the page in the troubleshooting work package(s), which address the particular symptom.
c.
Read each step before performing the test or inspection. Most troubleshooting procedures require isolation
and testing of multiple components. To achieve this, the tests are broken down as follows:
(1) Each Test Step contains a sequence number and a title (e.g., Test Step 1. Verify Operation of Driv-
ing Lights). The Test Step title describes the main action occurring in the subsequent test procedural
steps.
(2) Each numbered test procedural step describes a necessary action to carry out the diagnostic process
(e.g., 1. Turn ignition switch and battery disconnect switch to OFF position.).
(3) Perform each test step and subsequent test procedural steps and associated corrective action as
directed. Each corrective action will direct the troubleshooter to perform a repair, proceed to another
test procedural step, or proceed to another test step.
d. Refer to the Schematic Introduction (WP 0544) for an explanation of electrical and hydraulic schematics.
e. Refer to the Schematic Index (WP 0545) for a reference to each schematic foldout.
f.
Review the applicable electrical schematic (WP 0550, Item 138), and hydraulic schematic
(WP 0550, Item 139) before troubleshooting the machine.
0006-1
