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 324 of 1275

TM 9-2350-311-20-1

3-3 TROUBLESHOOTING CHART — CONTINUED

—

r.

ENGINE OIL PRESSURE GAGE CIRCUIT —

ENGINE OIL PRESSURE INDICATOR FAILS TO

CONTINUED

OPERATE WITH ENGINE RUNNING; ALL OTHER

INSTRUMENTS OPERATE — CONTINUED

CONTINUED FROM STEP B

I

I

G

1. Reconnect lead 36 to ENGINE OIL

PRESSURE gage.

2. Disconnect battery ground leads.

3. Disconnect bulkhead-to-portable instrument

panel harness from portable instrument

panel disconnect.

4. Place jumper wires from socket P (lead

459B) to socket C (lead 459) and from pin

A to socket A (lead 27).

5. Reconnect battery ground leads.

6. Turn MASTER switch ON and check

ENGINE OIL PRESSURE gage for reading.

7. If ENGINE OIL PRESSURE gage shows a

maximum reading, place a jumper wire from

pin D (lead 36) to ground.

8. Check gage for reading.

9. Turn MASTER switch OFF.

Does ENGINE OIL PRESSURE gage show minimum

when grounded and maximum when not grounded?

Repair or replace lead 36 from

portable instrument panel wiring

harness (para 8-57).

CONTINUED ON NEXT PAGE

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