TM 5-3805-248-23-1
TROUBLESHOOTING INTRODUCTION - CONTINUED
0004 00
ELECTRICAL TROUBLESHOOTING - GENERAL INFORMATION
NOTE
Refer to Electrical General Maintenance Instructions (WP 0018 00) for instructions on using a multimeter
to check for continuity or shorts and to perform voltage checks.
1.
Analyze the symptoms and conditions and determine the most likely cause for the problem, then troubleshoot that cir-
cuit first. The more information you have concerning the problem, the easier it will be to troubleshoot.
2.
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
3.
Frayed, broken, loose or corroded wiring is a common source of problems in any electrical circuit. Always make a
visual inspection before starting detailed troubleshooting. Observe in particular contacts to ground. Components with
case grounds can be especially troublesome.
CAUTION
When making continuity checks, ensure the test equipment is isolated from power source.
4.
Most checks made are voltage checks. Pay particular attention to voltages being checked in procedures. This equipment
is a 24 volt system. 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 jumper wires using jumper wire kit. When ready
to make the prescribed check, apply power to the circuit (if required). A helper may be required if the switch or power
source is out of reach. Release the power function prior to power going on, to avoid damage to equipment.
END OF WORK PACKAGE
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