Figure 2-22. Removal of MODE and TEST SELECT switch knobs.

TM 5-6675-250-34

Table 2-1. Troubleshooting-Continued

MALFUNCITON

TEST OR INSPECTION

CORRECTIVE ACTION

b. Unfasten ten screws securing the printed circuit board to mounting brackets and loosen the board to obtain access

to electrical connectors.

CAUTION

To avoid damage to the electrical connectors, alternately back-off each of the two attaching screws when removing the

connectors.

c. Disconnect two electrical connectors (2A2J5, 2A2J6) by unfastening two screws at each connector.

d. Check continuity between the input pins of the mode select switch and the position pins. Check voltage drop between

pin 2 of the theodolite bright control and pins 1 and 3 while rotating the control shaft.

If continuity is not present when checking the MODE SELECT switch and voltage drop exist when checking

theodolite bright control, replace them.

(1). Place MODE SELECT switch to GC position.

(2). Place TEST SELECT switch to SOURCE VOLTAGE positions.

(3). Loosen MODE SELECT and TEST SELECT knob setscrews with 5/64 and 0.050-inch hex

wrench, respectively, and remove knpb from switch shaft.

TS 006261

Change 1,

2-17

Figure 2-22. Removal of MODE and TEST SELECT switch knobs.