What do you mean by a twisted pair cable, one with just 4 wires connected (ie 2 pairs). The cheap cable testers just work on a continuity basis and the lights show when there is a connection. The lights are numbered so you know that 3 is connected to 3 on not 5 etc. Did you make the last cable yourself or was it bought. If it was purchased was it a cross over patch cable or a normal one.
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