TM-9-2350-311-20-2

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

TECHNICAL MANUAL; UNIT MAINTENANCE MANUAL FOR CAB, ARMAMENT, SIGHTING AND FIRE CONTROL, ELEVATING AND TRAVERSING SYSTEMS AND ASSOCIATED COMPONENTS

DECEMBER 1993

TM-9-2350-311-20-2 - Page 200 of 828

TM 9–2350–311–20–2

3–88

3–3

TROUBLESHOOTING

— CONTINUED

h.

CAB LIGHTING SYSTEM

The cab lighting system consists of three dome light assemblies and internal lighting for the M15 elevation quadrant,

M117/M117A2 panoramic telescope, and M118A2/M118A3 elbow telescope.

Power for these lighting components is routed from the contact arm assemblies through the gunner’s selector switch box

assembly.

LEGEND:

1. Electrical contact arm assemblies

2. Gunner’s selector switch box assembly

3. M117/M117A2 panoramic telescope

4. M118A2/M118A3 elbow telescope

5. M15 elevation quadrant

6. Dome light assemblies

147A

147B

147C

147

M118A2/M118A3

ELBOW TELESCOPE

M117/M117A2

PANORAMIC TELESCOPE

M15 ELEVATION

QUADRANT

GUNNER’S

SELECTOR

SWITCH BOX

100

100

100

DOME LIGHT (3)

138

PICTORIAL VIEW

ELECTRICAL DIAGRAM

2

1

3

1

6

1

4

6

1

5

6

CIRCUIT

BREAKER

100