TM 9-4120-378-14
4.15 MAINTENANCE OF ELECTRICAL SYSTEM.
4.15.1 The electrical system is made Up of:
a.
Heater Thermostatic Switch,
Heater Elements,
b.
Control Module and Components,
c.
Junction Box and Components,
d.
e.
f.
High/Low Pressure Cutout Switches,
Evaporator and Condenser Fan Motors Run Capacitors,
g.
Compressor Start and Run Capacitors,
h.
Compressor Start Relay,
i.
Wiring Harness, and
j.
Compressor Wiring.
k.
4.15.2 Electric assemblies and groups of associated components are covered in separate paragraphs.
Disconnect air conditioner power supply before doing maintenance work on the
electrical system.
4.15.3 Testing and Inspecting the Electrical System,
a. Troubleshooting procedures for testing the electrical system to isolate causes of trouble are discussed in
Table 4-1. More detailed test information is contained in specific paragraphs about the electrical components.
b. Use a continuity tester or a multimeter set on low-resistance range to test for continuity.
c. Use an insulation tester or a multimeter set on a high-resistance range to test for short circuits between the circuit
in a component and the outside casing of the component.
d. When testing an electrical component, check for visible damage and inspect all wiring in the area for damage or
loose connections.
