How to Test an Ethernet Cable

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This wikiHow teaches you how to test an Ethernet cable. To test an Ethernet cable, you need a cable tester. There are different models of cable testers you can purchase. Some have a detachable receiver unit that you can use to test a cable across two rooms.

Step 1 Purchase an Ethernet cable tester.

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Purchase an Ethernet cable tester. There are many models you can purchase. Make sure it has a battery in it and power it on.

Step 2 Plug one end of the cable into the transmit jack.

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Plug one end of the cable into the transmit jack. The transmit jack on the tester maybe be labeled "TX".

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Step 3 Plug the other end of the cable into the receiver jack.The receiver jack <a href=may be labeled " width="460" height="345" />

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Plug the other end of the cable into the receiver jack.The receiver jack may be labeled "RX" on the device. Some testers have a detachable receiver you can use to test the cable across different rooms. [1] X Research source

Step 4 Check the lights on the tester.

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Check the lights on the tester. Most testers will have 2 sets of 8 LED lights that correspond to the 8 pins on the transmitting and receiving end of the Ethernet cable. There will also be a G light for the ground. It will test each pin one at a time. If all 8 pins light up on both ends, the cable is good. If any of the lights do not light up on either end, this indicates a short in the cable. Don't worry if the G light doesn't light up. If the lights on either end flash out of order, this indicates that you are testing a crossover cable. As long as all 8 lights flash, the cable is good. [2] X Research source