TM-9-2350-261-20-1 Unit Maintenance Manual Volume 1 M113A2 M577A2 M1064 M1068 M1059 M901A1 Download
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TM 9-2350-261-20-1 HORN DOES NOT OPERATE — Continued 0037 00 4Y 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? 4YN 1. Install right headlight wiring harness plug to front main harness jack at fire wall. 2. Install horn ground lead plug to horn jack. 3. Install right headlight wiring harness circuit 25 plug onto horn jack. 4. Replace horn switch (WP 0252 00). 5. Verify no faults found. 5Y 1. Remove jumper wire from right headlight wiring harness circuit 25. 2. Install circuit 25 plug on horn jack. 3. Install a jumper wire between horn switch plug (1), circuit 25 pin (2), and ground. 4. Measure resistance between front main harness jack (3), pin A (4), and ground. 5. Does multimeter read 0 ohms? 5YN 1. Remove jumper wire from horn switch plug. 2. Repair front main harness circuit 25 (WP 0312 00). 3. Verify no faults found. 0037 00-4