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 WORKâContinued 0037 00 4Y 1. Install jumper wire between horn switch plug (1), circuit 25 pin (2) and ground. 2. Measure resistance between harness 12349881 jack (3), pin A (4) and ground. 3. Does multimeter read 0 ohms? YES NO 4YN 1. Remove jumper wire from horn switch plug. 2. Faulty harness 12349881 circuit 25A. Beyond unit maintenance repair. 3. Notify supervisor. 5Y 1. Remove jumper wire from horn switch plug. 2. Remove instrument panel for access (WP 0295 00). 3. Remove harness 12349881 circuit 25A plug (1) from cable assembly 12349858 circuit 25A jack (2). 4. Install jumper wire between 12349858 jack, circuit 25A pin (2) and ground. 5. Measure resistance between horn switch plug (3), circuit 25A pin (4) and ground. 6. Does multimeter read 0 ohms? YES NO 5YN 1. Remove jumper wire from harness 12349858 circuit 25A. 2. Faulty harness 12349881 circuit 25A. Beyond unit maintenance repair. 3. Notify supervisor. 0037 00-3