TM-9-2350-311-20-1

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

TECHNICAL MANUAL; UNIT MAINTENANCE MANUAL FOR HULL, POWERPLANT, DRIVE CONTROLS, TRACKS, SUSPENSION, AND ASSOCIATED COMPONENTS

AUGUST 1994

TM-9-2350-311-20-1 - Page 123 of 1275

TM 9-2350-311-20-1

(2) MASTER SWITCH INDICATOR LIGHT FAILS TO

OPERATE; MASTER SWITCH IS ON

Tools

General mechanic’s tool kit (item 64, Appx H)

Multimeter (item 36, Appx H)

TA-1 probe kit (item 43, Appx H)

Engine access doors open (TM 9-2350-311-10)

A

1. Remove MASTER switch indicator light

from socket.

2. Place red lead of multimeter in socket

and black lead to ground.

3. Turn MASTER switch ON, and check for

voltage.

4. Turn MASTER switch OFF.

Is voltage present?

Replace LED (para 8-17).

1. Disconnect lead 459L from MASTER

switch indicator light.

2. Place red lead of multimeter in lead 459L

and black lead to ground.

3. Turn MASTER switch ON, and check for

voltage.

4. Turn MASTER switch OFF.

Is voltage present?

Replace MASTER switch indicator

I

I

light socket (para 8-17).

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