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 2EY 1. Install heater harness on heater control box jack. 2. Remove heater harness 402A plug (1) from heater fuel pump jack (2). 3. Measure voltage between plug (1) pin and ground with HEATER switch on START. 4. Does multimeter read more than 17 volts? YES NO 2EYN 1. Faulty heater harness circuit 402. 2. Notify your supervisor. 3EY 1. Replace coolant heater fuel pump (WP 0475 00). 2. Verify no faults found. FY 1. Remove heater control box (WP 0474 00). 2. Measure resistance between lead ends of heater output jack (1) pin A (2) and ON/OFF/START switch terminal 14 (3). 3. Does multimeter read 0 ohms? YES NO FYN 1. Repair/replace faulty lead (WP 0294 00). 2. Verify no faults found. 0086 00-7