Table 5-1. Direct Support Troubleshooting Chart-Continued

TM 11-5895-1179-13 EE132-EA-OMP-010/E106 KY883 TO 31S1-2GSC-161

Item

Checks and

No.

Symptom

Probable Cause

Corrective Action

On-line

a. Defective display and

a. Replace display and

self-test

control circuit card

fails after

assembly A6A1.

assembly A6A1

all plug-

(paragraph 5-15).

in-circuit

b. Defective backplane

b. Replace backplane circuit

card assem-

circuit card assembly

card assembly A5A1

blies have

A5A1.

(paragraph 5-14).

been re-

placed.

One or more

a. Improperly seated or

a. Reseat plug-in-circuit

indicators

defective plug-in-

card assemblies. If

or one or

circuit card assembly.

fault remains, replace

more of the

plug-in-circuit card

ERROR RATE

assemblies one at a time

COUNTER dis-

(paragraph 4-7).

play LEDs

b. Defective display and

b. Replace display and

do not light

control circuit card

when the ON

assembly A6A1.

assembly A6A1

LINE/SELF

(paragraph 5-15).

TEST switch

c. Defective backplane

c. Replace backplane circuit

is in the

circuit card assembly

card assembly A5A1

LAMP TEST

A5A1.

(paragraph 5-15).

position.

An ON LINE

a. Defective electronic

a. Open front panel and

FAULT INDI-

signal A7DS1.

measure voltage at

CATOR il-

terminals 5 and 6 on

luminates

A7TB2 (figure 5-2).

but audible

Voltage should measure

alarm does

approx. 4.5 volts. If

not sound

voltage is present,

when FUNC-

replace electronic

TION select

signal (paragraph 5-16).

switch is

b. Defective I/O plug-in-

b. Replace I/O plug-in-

in other

circuit card assembly

circuit card assembly A3

than the

A3.

(paragraph 4-7).

SELF TEST

c. Defective display and

c. Replace display and

position.

control circuit card

assembly A5A1.

assembly (paragraph

5-15).

d. Defective electronic

d. Replace electronic

signal connector

assembly A8A2.

assembly A8A2

(paragraph 5-33).

5-6