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 449 of 1275

TM 9-2350-311 -20-1

(5) AIR PURIFIER, DRIVER’S AND CANNONEER NO. 2

NBC HEATERS FAIL TO OPERATE

T

OO

I

S

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 439 from NBC switch.

2. Place red lead of multimeter on NBC switch

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 439 of ventilated I

I

I face piece system power harness

I (para 8-62).

1

B

1. Reconnect lead 439 to NBC switch.

2. Disconnect lead 438 from NBC switch.

3. Place red lead of multimeter in lead 438

and black lead to ground.

4. Turn MASTER switch ON and check for

voltage.

5. Turn MASTER switch OFF.

Is voltage present?

I

I

1

Replace NBC switch (para 8-17).

1

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