Preliminary Procedures

TM 11-5820-477-30

2-4. preliminary Procedures (figure 2-1 )

Before troubleshooting can be performed, the control unit must be installed in a bench test setup. Refer to the

operator's and unit maintenance manual, TM 11-5820-477-12, for bench test setup data. For component checks,

perform the following:

a. Release the two front clamps and slide the remote or local control unit chassis out of its case.

b. Loosen four captive screws and remove component board A202 (remote control unit) or Al 02 (local control

unit) from chassis.

c. Place on bench without disconnecting connector P201 from J204 (remote control unit) or P102 from J104

(local control unit).

cf. Upon completion of tests, replace component board and secure with four captive screws.

e. Slide chassis into its case, close the two front clamps.

2-5. Dc Resistance of Transformers and Coils

Dc resistance readings are made with components disconnected. Determine resistance between terminals as

indicated in tables 2-1 and 2-2.

CAUTION

Do not make any resistance measurements on control units except as specified. Current

in multimeter battery can destroy transistors. In some cases, 0.1 volt applied between

base and emitter in reverse direction can destroy the transistor.

Table 2-1. Remote Control Unit Dc Resistance

Transformer or Coil

Terminals

Ohms

80 10%

T201

1-2

60 10%

3-4

70 10%

5-6

T202

1-2

125 20%

100 20%

3-4

75 20%

5-6

6-7

82 20%

5-7

50 20%

T203

1-2

5 25%

6 25%

2-3

4-5

0.9 25%

FL201

2.75 10%

1-2

FL202

1-2

2.75 10%

K201

480 10%

1-5

2-3