Multi-Network. Cable Tester. User Manual mode to “MANUAL” and then press the “TEST” button Plug one end of the cable into the modular jack on the. Multi-Network Cable Tester Pro .1,2,3,4,5,6. 7,8,9,10 LANtest. User Manual. MODELS: 256550 LANtest. 256551 LANtest Kit. Modular Cable test. This device requires the use of a 9V battery (not included–see Product Profile part J To test RJ11 and RJ12 cables, follow the same instructions as theEasy verification for cabling faults including discontinuity, open wires, shorts (short-circuited - wire/wire or wire/shield - connections), miswiring and