TM-9-2350-311-10

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; OPERATOR’S MANUAL

NOVEMBER 1994

TM-9-2350-311-10 - Page 437 of 775

TM 9--2350--311--10

3--37

3--6

ARMAMENT AND CAB MAINTENANCE — CONTINUED

3--6.1

Maintenance of Sighting and Fire Control Equipment — Continued

b. Care — Continued

4

In below-freezing weather, optical surfaces should be cleaned with lens paper (item 33, Appx D)

moistened with optical lens cleaning compound (item 9, Appx D). If cleaning compound is not available,

use dry lens paper. Don’t breathe on lens. Wipe gently to avoid scratching or removing the lens coating.

FM 9--207 contains cold-weather maintenance instructions on fire-control materiel.

c. Instrument Light

1

Operate switches (1) to check operation of LEDs (2) on M117/M117A2 panoramic telescope (3),

M145/M145A1 telescope mount (4), M15 elevation quadrant (5), and M118A2/M118A3 elbow telescope

(6).

2

Check brightness of reticle LEDs with variable resistor knobs (7 and 8).

3

Inspect electrical leads and connections for damaged or frayed insulation. Properly connect or stow as

required.

1

3

4

5

6

8

2

1

2

2

2

2

7

2

2