TM-9-2540-207-14&P Sustainment Manual for A20 Heater for M113 2540-01-396-2826 Download
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TM 9-2540-207-14&P 6-16 6.5.21 E1 - LOW VOLTAGE (Design Iteration 1 & 2 Only) VOLTAGE SUPPLIED TO THE HEATER IS BELOW NORMAL VOLTAGE LIMITS (19VDC - 28VDC NORMAL RANGE) CHECK/POSSIBLE CAUSE REF. REPAIR 1 CHECK THE SOURCE VOLTAGE OR BATTERY LEVELS. IF VOLTAGE IS LESS THAN 19VDC THEN OPERATE HEATER WITH VEHICLE RUNNING 2 WITH HEATER OFF, CHECK FOR FREE ROTATION OF THE VENT IMPELLER BY MANUALLY SPINNING BY HAND 5.2.6 5.2.4 IF IMPELLER DOES NOT SPIN FREELY, REPLACE VENT FAN MOTOR AND VENT FAN IMPELLER RESTART HEATER 3 CHECK ELECTRICAL INPUT CONNECTIONS FOR LOOSE WIRES 2.5 5.5.6 RECONNECT ALL ELECTRICAL CONNECTIONS TO WIRING HARNESS RESTART HEATER 4 DEFECTIVE ELECTRONIC VENT FAN DRIVER BOARD 5.2.5 REPLACE ELECTRONIC VENT FAN DRIVER BOARD RESTART HEATER 5 DEFECTIVE WIRING HARNESS 5.5.6 REPLACE WIRING HARNESS RESTART HEATER 6.5.22 E1 - LOW VOLTAGE (Design Iteration 3 Only) VOLTAGE SUPPLIED TO THE HEATER IS BELOW NORMAL VOLTAGE LIMITS (19VDC - 28VDC NORMAL RANGE); LOW VOLTAGE OR LOW VOLTAGE IN VENT ONLY CHECK/POSSIBLE CAUSE REF. REPAIR 1 CHECK THE SOURCE VOLTAGE OR BATTERY LEVELS. IF VOLTAGE IS LESS THAN 19VDC THEN OPERATE HEATER WITH VEHICLE RUNNING 2 CHECK POWER INLET SIDE OF THE START/OFF/RUN SWITCH TO HAVE GREATER THAN 19 VDC IF VOLTAGE IS LESS THAN 19VDC THEN OPERATE HEATER WITH VEHICLE RUNNING 3 CHECK THAT THE PROPER GAUGE OF WIRE IS USED FOR THE LENGTH OF CIRCUIT. REQUIREMENT IS 12 AWG FOR < 12 FT; FOR LONGER CIRCUITS THE RESISTANCE MUST BE LESS THAN OR EQUAL TO 12 AWG @ 12FT. INSTALL PROPER GAUGE OF SUPPLY WIRE RESTART HEATER 4 CHECK ELECTRICAL INPUT CONNECTIONS FOR LOOSE WIRES RECONNECT ALL ELECTRICAL CONNECTIONS TO HEATER RESTART HEATER 5 CHECK VOLTAGE ON OUTLET SIDE OF FILTER BOARD WITH POWER SUPPIED TO HEATER VOLTAGE BETWEEN GROUND (J2-PIN1) AND HOT WIRE (J2-PIN3) SHOULD EQUAL THE VOLTAGE SUPPLIED IF THE VOLTAGE IS LOW REPLACE THE FILTER BOARD RESTART HEATER 6 CHECK VOLTAGE AT THE POWER BOARD INLET VOLTAGE BETWEEN GROUND (J7) AND HOT WIRE (J2) SHOULD EQUAL THE VOLTAGE SUPPLIED IF THE VOLTAGE IS LOW REPLACE THE POWER BOARD RESTART HEATER