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 208 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

1. Reconnect hose to pump and motor

assembly.

2. If air box heater, fuel solenoid, and

pump and motor assembly all failed to

operate, go to step Q.

3. If air box heater and pump and

motor assembly both failed to operate, go

to step L

4. If only air box heater failed to operate,

go to step E.

5. If only pump and motor assembly failed

to operate, go to step G.

6. If only fuel solenoid failed to operate, go

to step L.

1. Disconnect lead 486 from flame heater

ignition coil assembly.

2. Place red lead of multimeters on pin A (lead

486) and black lead to ground.

3. Turn MASTER switch ON and check for

voltage.

4. Turn MASTER switch OFF.

Is voltage present?

Replace flame heater ignition coil

assembly (para 5-10).

3-108