How do I do an isolation test to fix my ADSL or VDSL Connection?

When your internet is slow or not working at all, an isolation test can often fix your problem straight away! We might also ask you to do one so that we can see whether the issue you’re having is being caused by something within your home (e.g. one jackpoint or a cable) or whether it is something we will have to send a technician out to look at on the Chorus Network.


To carry out this isolation test you will need:


Please follow the steps below to carry out the isolation test:


  1. Connect your modem via either the ADSL filter and Grey DSL cable, or via the Black VDSL cable to the first jackpoint
  2. The jackpoints should look like either one of the images below:

BT Jackpoint (most common)

RJ45 Jackpoint (newer properties)


  1. Turn off the WiFi on your computer and then connect your computer to the modem via the Yellow Ethernet cable to LAN1
  2. Ensure that everything else using the line is removed such as phones, Sky decoders and phone extension cables etc.
  3. Keeping these removed, plug in and turn on the power to your Skinny modem. Please ensure that the power button on the modem itself is turned on as well
  4. Once this has finished powering on, the lights on the Skinny modem should look as below:
  1. If you do see the above from the lights on the modem, please try browsing the internet. Are you able to connect?
  2. If the answer is no then please unplug the power to the modem, the computer from the Ethernet port and the cable/filter from the jackpoint and move to the next jackpoint in the property
  3. Please complete the above steps in order until you have exhausted all of the jackpoints in the your property

If you can carry out this test prior to contacting us then it will speed up us being able to resolve the issue for you. There is also the chance that the problem is resolved by this and you no longer need to contact us.

Article ID: 379
Created On: Wed, Dec 21, 2016 at 12:12 PM
Last Updated On: Wed, Aug 26, 2020 at 12:57 PM

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