Table 4-1. Preventive Maintenance Checks and Services

TM 55-4920-431-13

A-Annually

Item

Interval

To Be

Procedures

Item

No.

Inspected

NOTE

Procedures for gaining access

to inside of case are described

in paragraph 4-7.

Relay

Check for tightness in socket and that hold

down spring is in place. Check for loose

(1, fig 5-3)

wire connections

Analog

Check that harness is properly attached. Check

Converter

for broken wires and deteriorated insulation.

(19, fig 5-1)

Check screws (20, fig 5-1) for tightness.

Fuses

Check that fuses are proper size and type

(7, fig 5-3)

and in place in fuseblock (11, fig 5-3)

Meters

Verify accuracy in accordance with

(1, 2, fig 5-2)

paragraph 4-30.

NOTE

Foldouts are located at back of manual

Section III. TROUBLESHOOTING

4-6. Introduction. The following troubleshooting procedures are to find and correct faults

in the tester itself, and not in the APU or ESU being tested. Additional continuity checks

can be performed by using schematic diagram, figure FO-1 and wiring diagram, figure

FO-2, and by testing in accordance with paragraph 4-8. Refer to figure 3-1 for

identification of connector contacts.

NOTE

Refer to wiring diagram, figure FO-2 to locate compo-

nents, wires, connectors, pins and terminals where

test connections are to be made. The wiring diagram

covers only internal wiring of the tester. Refer to

schematic diagram, figure FO-1, for wiring of

harnesses.

4-2