How to Troubleshoot an Ethernet Cable That is Not Connecting
- 1). Compare both ends of the cable. If all of the colored wires on one plug are in the same position as on the other plug, you have a straight-through cable. If not, it is a crossover cable. Make sure you are using the correct cable for the application. If you have a spare cable, try substituting that cable and see if the problem is fixed.
- 2). Turn on the multimeter and set it to the lowest resistance setting available.
- 3). Start with the first wire in one of the plugs. Hold one of the test leads on the first pin in one of the connectors and touch the other test lead to the same colored pin in the other connector. If you get zero, or a very low resistance measurement, that wire is ok.
- 4). Repeat step 3 for the remaining wires. If you get a high reading on one or more wires, the cable is defective. Look closely at the plug on each end of the cable to see if any of the wires are loose or broken. If they are, you can cut the end off and install a new plug. If you cannot see the problem, you can cut off both ends and install new plugs or replace the cable.
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