Section V. TROUBLESHOOTING

TM 9-4931-378-13&P

Section V. TROUBLESHOOTING

5-8. Introductory Information.

through W5 and the power cable adapter shall be per-

a. This section contains procedures for Iocating and

formed.

correcting operating troubles which may develop in the

a. AC Power Cable W1 Checkout. Using the DVM

test set. The procedures are presented in a logical order.

T a b l e s 5-1 through 5-3 are test set cable wire lists

set to read resistance in conjunction with figure

5-1, check for continuity (less than one Ohm) be-

Performing the checkout as presented WiII assure you

that the test set is operational Each malfunction of a

tween interconnected connector pins. Unless

shop replaceable unit (SRU) or component is related to

otherwise noted, the resistance to all other pins or

actions listed in table 5-4 which will help you correct the

to the connector shells should be in the megohm

problem. Table 5-4 lists malfunctions in checkout order.

range. Flexing the cabie while making resistance

You should perform the checkout in the order of

checks will aid in isolating intermittent connec-

presentation. When you have performed a corrective

action, repeat the checkout procedure which Indicated

tions.

the trouble before you continue with the checkout.

DC Power Cable W2 Checkout. Using the DVM in

b. The failure isolation shop set (FISS) electronic

conjunction with figure 5-2, check for continuity

circuit board: Air Data Subsystem provides slave boards

between interconnected connector pins. Unless

for use during troubleshooting to aid in the identification

otherwise noted, the resistance to all other pins or

of faulty circuit board assembles within the line replace-

able unit (LRU), once the faulty circuit board has been

to the connector shells should be in the megohm

identified, the slave board is returned to the shop set for

range. Flexing the cable while making resistance

future use and a replacement board is requisitioned for

checks will aid in isolating intermittent connec-

the LRU.

tions.

c. This manual lists the most likely malfunctions. If

Power Cable Adapter W6 Checkout. Using the

a malfunction is not listed (except for obvious malfunc-

DVM in conjunction with figure 5-3, check for

tions and causes), or is not corrected by listed corrective

actions, notify the next higher level of maintenance.

continuity between interconnected connector

Disassembly and reassembly procedures are in Chapter

pins. Unless otherwise noted, the resistance to all

other pins or to the adapter shell should be in the

d. To assist you in troubleshooting, figure FO-1

shows the test set schematic.

5-9. Cabie Checkout. Before connecting power to the

test set, a point-to-point continuity check of cables W1

tween interconnected connector pins. Connector

pin patterns are shown in figure 5-4. Unless other-

wise noted, the resistance to all other pins and to

the connector shells should be in the megohm

5-2

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