TM-9-2350-277-20-1 Unit Maintenance Manual Volume 1 M113A3 M577A3 M1064A3 M1068A3 M58 Download
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TM 9-2350-277-20-1 HORN DOES NOT WORK—Continued 0037 00 2Y 1. Release horn button. 2. (H) Move MASTER POWER switch to OFF. 3. Remove harness 8763491 plug (1) from harness 12349881 jack (2) at fire wall. 4. Measure resistance between harness 8763491 plug (1), pin A (3) to lead 25 (4). 5. Does multimeter read 0 ohms? YES NO 2YN 1. Replace wiring harness 8763491 circuit 25 (WP 0373 00). 2. Verify no faults found. 3Y 1. Remove circuit 25/25A plug (1) from horn switch jack (2). 2. Measure resistance between horn switch jack pins (2) with horn switch depressed. 3. Does multimeter read 0 ohms? YES NO 3YN 1. Install harness 8763491 plug to harness 12349881 jack at fire wall. 2. Install lead 10863474 plug to horn jack. 3. Install harness 8763491 circuit 25 plug onto horn jack. 4. Replace horn switch (WP 0293 00). 5. Verify no faults found. 0037 00-2