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 448 of 1275

TM 9-2350-311 -20-1

3-3 TROUBLESHOOTING CHART —

CONTINUED

af. VENTILATED FACE PIECE SYSTEM CIRCUIT —

(4) CANNONEER NO. 2 NBC HEATER FAILS TO

CONTINUED

OPERATE; PURIFIER AND DRIVER’S NBC HEATER

OPERATE PROPERLY

INITIAL SETUP

Tools

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

Multimeter (item 36, Appx H)

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

A

1. Disconnect lead 439C from cannoneer no. 2

NBC heater.

2. Place red lead of multimeter in lead 439C and

black lead to ground.

3 Turn MASTER and NBC switches ON and

check for voltage.

4. Turn MASTER and NBC switches OFF.

Is voltage present?

I

I Repair or replace lead 439C of

ventilated face piece system power

wiring harness (para 8-62).

#

Replace cannoneer no. 2 NBC heater

(para 12-3).

END OF TASK

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