TM-9-2320-272-10

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; OPERATOR'S MANUAL

SEPTEMBER 2004

CHANGE 2

TM-9-2320-272-10 - Page 366 of 481

TM 9-2320-272-10

Change 2

3-17

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Table 3-1. Troubleshooting (Contd).

Step 5. Check engine oil level.

If low, add oil (para. 2-10).

Step 6. Check radiator fan clutch operation.

If fan blade is not turning, install override lockup bolts (para. 3-14).

FUEL BURNING PERSONNEL AND ENGINE COOLANT HEATER KITS

45. FUEL BURNING PERSONNEL HEATER FAILS TO START WHEN RUN-OFF-START

SWITCH IS HELD IN START POSITION.

WARNING

Exhaust gases can kill. Do not operate engine coolant

heater in closed area occupied by personnel. Such

action will result in injury or death.

NOTE

Heater will not operate if RUN-OFF-START switch is

moved to RUN position before indicator lamp illuminates.

Step 1. Press PRESS-TO-TEST button on heater control box to check

operation of circuit.

If indicator lamp does not illuminate, notify unit maintenance.

Step 2. Check to see if HI-LO switch on heater control box is set to HI.

If not, set HI-LO switch to HI.

Step 3. Check fuel level on fuel gauge.

Fill fuel tank(s) if necessary.

Step 4. Check to see if electric fuel pump shutoff valve is closed (para. 2-44).

If closed, open fuel pump shutoff valve.