Section II. TROUBLESHOOTING CHARTS
PRELIMINARY TROUBLESHOOTING PROCEDURES
Fluid leaks are classified as either Class I, Class II, or Class IIl:
Class I: Seepage of fluid, as indicated by wetness or discoloration, not great enough to form
Class II: Leakage of fluid great enough to form drops, but not enough to cause drops to drip from
the item being checked or observed.
Class IIl: Leakage of fluid great enough to form drops that fall from the item being checked or
Before starting any specific troubleshooting procedures, perform the following:
Visually check for ruptured oil hoses or tubes, and for Class II or Class III leaks.
Check for mechanical jamming or binding caused by rocks or other foreign matter.
Check fluid levels in subject area and service as required (TM 9-2320-363-10 or page 2-3, Unit PMCS in this manual).
RELIEVING HYDRAULIC SYSTEM PRESSURE (M916A1 AND M916A2)
Cycle controls a few times with hydraulic power off to relieve any residual pressure in lines.
Before you start detail troubleshooting procedures, review the wiring diagram to thoroughly familiarize yourself with
the circuit(s) involved. Analyze the symptoms and conditions and use common sense and logic to determine the most
likely cause for the problem, then troubleshoot that circuit first. The more information you have concerning the problem,
the easier it will be to troubleshoot.
Isolate to the subsystem level (in cases where more than one subsystem is involved); next, isolate the problem to a
single circuit within the subsystem; then, isolate the problem to the faulty component using the troubleshooting symptom
Frayed, broken, loose, or corroded wiring is a common source of problems in any electrical circuit. Always make
visual inspection before starting detail troubleshooting. Observe in particular, contacts to ground. Components with case
grounds are especially troublesome.
Most of the checks are made by voltage checks. Pay particular attention to the voltages being checked in the
procedures. This equipment has a combination of 12 and 24 volt systems.
Instructions prior to the step instruct to disconnect at test point from the potential malfunctioning component. Once
the check has been made, either repair the component or go to the referenced step. If going to another step, reconnect
connection or do as otherwise instructed, such as install
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