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 390 of 1275

TM 9-2350-311-20-1

3-3 TROUBLESHOOTING CHART — CONTINUED

z.

PERSONNEL HEATER CIRCUIT — CONTINUED (1) PERSONNEL HEATER FAILS TO OPERATE —

CONTINUED

CONTINUED FROM STEP G

I

2.

3.

4.

5.

Reconnect lead 400A to circuit breaker

output.

Disconnect lead 400A from HEAT

SELECTOR switch.

Place red lead of multimeter in lead 400A and

black lead to ground.

Turn MASTER switch ON and check for

voltage.

Turn MASTER switch OFF.

I

Is voltage present?

1.

2.

3.

4.

5.

6.

7.

1

I

Reconnect lead 400A to HEAT SELECTOR

switch.

Disconnect both leads 402 from HEAT

SELECTOR switch terminals.

Place red lead of multimeter on HIGH

terminal and black lead to ground.

Turn MASTER switch ON, HEAT

SELECTOR switch to HIGH and check for

voltage.

Place red lead of multimeter on LOW terminal

and black lead to ground.

Turn MASTER switch ON, HEAT SELECTOR

switch to HIGH and check for voltage.

Turn MASTER and HEAT SELECTOR

switches OFF.

Is voltage present in both positions?

•

Replace heat selector switch (para 8-20).

I

I

1

CONTINUED ON NEXT PAGE

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