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I've recently helped a friend wire his new office up with Ethernet cable wall sockets that all connect to a central patch panel. The issue I currently have is with testing the cable.. I receive the following results:

Master Tester (regardless of which end is is plugged into)

Pin 1 - Pin 8 in order, no problems.

Remote Tester

Pin 1
Pin 2
Pin 2 & 3
Pin 4 & 5
Pin 5
Pin 6 & 7
Pin 6 & 7
Pin 8

I have tested it on other cables that work fine so the remote tester is working correctly.

The setup I have is:

Master Tester -> Ethernet Cable (pre-tested) -> Patch Panel -> Trunked Ethernet Cable -> Wall Socket -> Ethernet Cable (pre-tested) -> Remote Tester

I've never used a tester that displays multiple lights (I have a digital one at work). Does anyone have any ideas to what could be the issue without ripping both (hard to access) ends out again?

Just to repeat, it's the same output regardless of which end the master/remote testers are placed.

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Why does Pin 3 show as 2&3 but Pin 2 not? And why does Pin 4 show as 4&5 but Pin 5 not? Are you sure that your tester is accurate? – Andrew Nov 16 '11 at 6:12

Something could be screwed up on the punchdown block (in back). If you patch to a different wall drop does the test go okay? That will help you isolate where the issue is.

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