Table 2-2 TROUBLESHOOTING

TM 11-5805-387-20-2

Table 2-2 TROUBLESHOOTING

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. No +20 volt dc indication on front panel meter

Step 1. See if circuit breaker is tripped.

CAUTION

To prevent damage to the equipment, do not hold ON/OFF circuit breaker

switch on front panel in ON position.

Reset circuit breaker switch to ON.

If it trips again, higher category maintenance required.

Step 2. Use Multimeter AN/URM-105 to check for 28 volts dc between pins A (+) and C ()

of POWER input cable.

Turn circuit breaker ON/OFF switch to OFF.

Disconnect POWER cable from primary

power connector.

Connect multimeter as shown in figure.

POWER

CABLE

If 28 volts dc is absent, replace POWER cable.

MULTIMETER

AN/URM-105

If 28 volts dc is present, go to 2.

2. No +20 volt dc indication on front panel meter but primary power input normal

Step 1. Be sure modules are securely seated in their sockets.

CHASSIS INTERIOR, TOP VIEW

Securely seat all modules in their sockets.

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