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 6-10 4 CHECK WIRE HARNESS FOR CONTINUITY AND SHORTS CHECK 2 WIRES FROM THE VENT FAN BOARD TO THE LOGIC BOARD FOR CONTINUITY: P11-PIN12 TO P1-PIN3 P11-PIN4 TO P1-PIN12 CHECK FOR MV SIGNAL BETWEEN P11-PIN13 AND P11-PIN5 FOR BT SENSOR P11-PIN14 AND P11-PI N 6 FOR XT SENSOR CHECK FOR A MINIMUM OF 150K RESISTANCE OR OPEN LINE BETWEEN P11-PIN13 TO CHASIS GROUND AND P11-PIN14 TO CHASIS GROUND IF ANY CHECK FAILS REPLACE WIRE HARNESS RESTART HEATER COMPLETE THE FOLLOWING CHECKS AT ROOM TEMPERATURE AND WITH THE SENSOR HEATED TO GREATER THAN 600C. CHECK FOR MV SIGNAL BETWEEN P11-PIN13 AND P11-PIN5 FOR BT SENSOR P11-PIN14 AND P11-PIN6 FOR XT SENSOR CHECK FOR GREATER THAN 10K RESISTANCE BETWEEN; P11-PIN13 TO CHASIS GROUND AND P11-PIN14 TO CHASIS GROUND IF ANY CHECK FAILS REPLACE WIRE HARNESS RESTART HEATER 4 CHECK VENT FAN BOARD FOR LOOSE SOLDER JOINTS REPLACE VENT FAN BOARD RESTART HEATER 5 CHECK LOGIC BOARD FOR LOOSE SOLDER JOINTS REPLACE LOGIC BOARD RESTART HEATER NOTE: THIS FAULT MAY OCCUR ONLY WHEN THE SENSOR IS HEATED TO OPERATING TEMPERATURES. AFTER COOLING THE FAULT CAN CLEAR ALLOWING THE UNIT TO BE STARTED, OPERATING BREIFLY UNTIL THE SENSOR IS HEATED.