TM 9-2320-361-10 Table 3-1. Troubleshooting (Contd) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 41. POWER PLANT HEATER FAILS TO START WHEN RUN-OFF-START SWITCH IS HELD IN START POSITION. Exhaust gases can kill. Do not operate power plant heater in closed area occupied by personnel. Doing this may result in injury or death to personnel. CAUTION Do not operate fuel burning personnel heater and power plant heater at the same time. Doing this may result in overworked electric fuel pump. NOTE If RUN-OFF-START switch is turned to RUN position before red indicator light illuminates, heater will not operate. Step 1. Step 2. Step 3. Press PRESS-TO-TEST button on heater control box to check operation of circuit. If red indicator light does not illuminate, notify your supervisor. Check fuel level on fuel gage. Fill fuel tank if necessary. Check to see if power plant heater shutoff cock is closed. Refer to para. 2-6c. Open power plant heater shutoff cock. NOTE Select HI position if engine is cold. Select LO position if engine is already well heated. When in HI position, heater will automatically change to LO position when coolant temperature exceeds 190°F, and automatically change to HI position when coolant temperature drops below 120°F. 42. HEATER FAILS TO CONTINUE BURNING. Check fuel level on fuel gage. Fill fuel tank if necessary. 43. WINDSHIELD DEFROSTERS NOT OPERATING. Step 1. Check adjustment of defroster control handle. Adjust defroster control handle. Step 2. Check for restrictions in defroster deflectors. Clear restriction. 44. ENGINE OIL PAN SHROUD NOT RECEIVING HEAT (POWER PLANT HEATER ONLY). Step 1. Check to see if power plant heater is operating. Refer to para. 2-48. Start heater. If inoperative, notify your supervisor. 3-14