TM-9-2350-247-20-1 Unit Maintenance Manual Volume 1 M548A1 M548A3 Tracked Cargo Carrier Download
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TM 9-2350-247-20-1 COOLANT HEATER MALFUNCTIONS—Continued 0086 00 2BY 1. Remove rear main harness circuit 400A plug (1) from control box jack (2). 2. Measure voltage between main harness circuit 400A plug (1) pin and ground. 3. Does multimeter read more than 17 volts? YES NO 2BYN 1. Repair main harness circuit 400 between master switch and heater control box (WP 0294 00). 2. Verify no faults found. 3BY 1. Remove heater control box (WP 0474 00). 2. Measure resistance between lead ends from circuit breaker terminals 16 (1) and 17 (2). 3. Does multimeter read 0 ohms? YES NO 3BYN 1. Replace heater circuit breaker (WP 0472 00). 2. Verify no faults found. 0086 00-3