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 205 of 828

TM 9–2350–311–20–2

Change 2

3–93

h.

CAB LIGHTING SYSTEM

— CONTINUED

(3)

M145/M145A1 TELESCOPE MOUNT AND

M117/M117A2 PANORAMIC TELESCOPE

LIGHTS ARE OUT, BUT ALL OTHER LIGHTS

OPERATE.

INITIAL SETUP

Test Equipment

Multimeter (item 6, Appx H)

Tools

Artillery and turret mechanic’s tool kit

(SC 5180–95–CL–A12)

Equipment Condition

Vehicle MASTER switch to OFF (TM 9–2350–311–10)

Repair ground lead (para

8–3).

1.

Check ground lead for good connection.

2.

Place red multimeter lead in one socket and

black lead in ground socket of wire 147B.

3.

Check for voltage.

Is battery voltage present?

Replace wire 147B (para

8–3).

yes

no

A

yes

no

CONTINUED ON NEXT PAGE

B

WIRE 147B

M145/M145A1

TELESCOPE

MOUNT

1.

Disconnect wire 147B at M145/M145A1

telescope mount.

2.

Turn MASTER switch to ON.

3.

Place red multimeter lead in each socket of wire

147B and black lead to ground.

4.

Check for voltage.

Is battery voltage present at one socket only?

WIRE 147B

–

+

+

–