Fix broadband connection faults

Test if your BT line is working

One of the first things to try is to check if your broadband problems are related to your incoming BT line (if it does, the problem isn't something you can fix yourself - you'll need to speak to BT or your ISP).

The majority of people in the UK have an NTE5 master socket (at which BT wiring ends and yours begins). You can easily unscrew the lower half of this and remove the faceplate. Doing so will disconnect all of the internal wiring and give you access to a test socket on the right which provides a direct link to the incoming BT line.

Plug your microfilter into this and connect your broadband router/modem. If your problems are instantly fixed, you know the problem relates to your internal wiring or microfilters.

Check your internal wiring is correctly set up

If you have problems with your broadband randomly disconnecting or slow connection speeds, it could be caused by your extension socket wiring.

Unscrew the faceplate of your master socket and look at the wires on the back of it. Only 2 and 5 should be connected. 1 and 6 are not needed in the UK and 3 and 4 are now obsolete.

If any of those wires are connected, gently pull them out, being careful not to disconnect 2 and 5. Screw the socket back together.

You will need to repeat the process with all the extension sockets in your house.

Add a microfilter to the test socket

If your broadband works fine when connected to the master test socket, but not when the faceplate is put back on, there is a simple solution. It's not pretty and won't be to everyone's tastes, but it works well. Simply remove the faceplate, plug your microfilter into the test socket, and then plug the faceplate's connector into the microfilter output. Finally connect your broadband cable to the filter.

Replace the master socket faceplate and check your microfilters

If adding a microfilter to the test socket all works fine but you want a tidier option, consider buying an NTE5 ADSL faceplate from Solwise ADSL Splitters, Microfilters & Telecoms or ADSL Nation. They are very easy to fit.
Incorrectly placed microfilters are the cause of the majority of broadband errors. Every used phone socket in your house must have a microfilter fitted to it. If you use a splitter, plug the microfilter into the wall socket first, then connect the splitter to the microfilter. Don't get overzealous with filters though. If you have two on a single phone socket, or an extension cable, this could cause problems.

Is there a problem with the line?

If you're suddenly having trouble connecting to the internet and you can hear noise on the line, it could well be a fault. BT can check this and identify the nature of the problem and its location (inside your house, outside, or at the exchange). To report a suspected fault either phone 151 from a BT line (or 0800 800 151) on a mobile or BT online fault checker.

Line noise is probably caused by your microfilters either being faulty or not being connected properly (don't forget devices like Sky digiboxes and fax machines also need a filter). To troubleshoot the problem, disconnect all your ADSL equipment, including any filters so your telephone is all that's connected.

Check if the noise persists (you can do a quiet line test by dialling 17070 and selecting option 2). If it does, it's a line problem so contact BT. If it doesn't, connect your microfilter to the BT master socket, connect the phone and listen again. If you hear noise the filter is probably faulty, try another one.