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 212 of 1275

TM 9-2350-311-20-1

3-3 TROUBLESHOOTING CHART — CONTINUED

h. FLAME HEATER CIRCUIT (ENGINE MODEL

FLAME HEATER DOES NOT OPERATE — CONTINUED

7083-7396) — CONTINUED

CONTINUED FROM STEP I

2.

3.

4.

5.

6.

7.

8.

Reconnect FLAME HEATER switch lead

to bulkhead-to-portable instrument panel

wiring harness.

Disconnect battery ground leads.

Disconnect bulkhead-to-portable instrument

panel wiring harness from driver’s bulkhead.

Place a jumper wire from pin B to socket B

(lead 400-459B).

Place red lead of multimeters on pin C

(lead 486) and black lead to ground.

Reconnect battery ground leads.

Turn MASTER and FLAME HEATER

switches ON and check for voltage.

Turn MASTER and FLAME HEATER

switches OFF.

Is voltage present?

Repair or replace lead 486 of

bulkhead-to-portable instrument

panel wiring harness (para 8-49).

1. Reconnect bulkhead-to-portable instrument

panel wiring harness to driver’s bulkhead.

2. Disconnect engine disconnect to bulkhead

wiring harness from engine disconnect

bracket.

3. Place red lead of multimeters in socket A

(lead 486) and black lead to ground.

4. Turn MASTER and FLAME HEATER

switches ON and check for voltage.

5. Turn MASTER and FLAME HEATER

switches OFF.

Is voltage present?

CONTINUED ON NEXT PAGE

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