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 426 of 1275

TM 9-2350-311 -20-1

3-3 TROUBLESHOOTING CHART — CONTINUED

ae. ELECTRIC FUEL PUMP CIRCUIT —

CONTINUED ENGINE MISSES WHEN LOW ON FUEL; ONE OR BOTH

FUEL PUMPS FAIL TO OPERATE

Personnel Required

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

Two

Multimeter (item 36, Appx H)

Equipment

Condtlons

Hose (item 29, Appx H)

Engine access doors open (TM

(Long test leads may be needed for some tests;

Powerplant removed (para 4-5)

16 AWG wire maybe used as an extension.)

WARNING

Do not use open flame or smoke when working on fuel

system. An explosion may occur, causing severe injury

or death.

I

m

NOTE

Left fuel pump can be tested from driver’s access panel.

Powerplant must be removed to test right fuel pump.

I

Disconnect lead 76B from relay oil pressure

2. Place red lead of multimeter in lead 76B and

black lead to ground.

3. Turn MASTER switch ON and check for

voltage.

4. Turn MASTER switch OFF.

Is voltage present?

I Replace in-tank fuel pump system I

I relay (para 8-35).

RELAY OIL

PRESSURE

9-2350-311-10)

CONTINUED ON NEXT PAGE

INITIAL SETUP

Tool s

1 .

switch.

A

3-326