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 398 of 1275

TM 9-2350-311-20-1

3-3 TROUBLESHOOTING CHART — CONTINUED

aa. PERSONNEL VENTILATION BLOWER CIRCUIT —

PERSONNEL VENTILATION BLOWER FAILS TO

CONTINUED

OPERATE — CONTINUED

CONTINUED FROM STEP C

D

1. Reconnect accessory control box-to-heater/

blower wiring harness to ventilation blower.

.

2. Disconnect accessory control box-to-heater/

blower wiring harness from accessory control

box.

3. Place a jumper wire from socket B (lead

159B) to ground.

4. Place red lead of multimeters in socket A (lead

159A) and black lead to ground.

5. Turn MASTER switch ON, VENTILATOR

BLOWER switch in EXHAUST position and

check for voltage.

6. Place VENTILATOR BLOWER switch in

INTAKE position and check for voltage.

7. Turn MASTER and VENTILATOR BLOWER

switches OFF.

Is voltage present?

Go to step G.

E

1. With connections and VENTILATOR

BLOWER switch in positions where voltage

was obtained in step D, move black lead of

multimeters to socket C (lead 159C).

2. Turn MASTER switch ON and check for

voltage.

3. Turn MASTER switch OFF.

Is voltage present?

CONTINUED ON NEXT PAGE

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