Cross Connect Guide

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Cross Connect Guide

This article is a more in-depth companion piece to our Fusion Self-Install Guide. Following the delivery of a new DSL phone line to the MPoE (Main Point of Entry - otherwise known as the phone box), many circuits still require what is called a cross connect. A cross connect ties the outside and inside wiring together via binding posts. This will complete the circuit and deliver the DSL and phone signals from Sonic up to the jack where the modem will connect. This guide will show you how to identify the relevant wiring within the MPoE and how to complete the cross connect. Please note that this guide is for single-line DSL service; a two-line bonded installation will be more complicated and is likely to require a full installation from a Sonic technician.


Needle-nose pliers and a flathead screwdriver should be the only necessary tools to complete the cross connect. Gather these before heading out to your MPoE.

Tools for FSI.PNG


This can typically be found on one of the exterior walls of the home. In some instances, it may also be located in a garage, closet, etc. Once you find the MPoE we can open it up and get to the wiring inside. It is important to note that MPoE's are generally divided into an external side for ISP use and internal side for end user use.


An MPoE in it's natural habitat


  • The interior of an MPoE can be divided into two sections: one for connecting the external wiring provided by your ISP, and the other for connecting the internal wiring of your home.
Open mpoe IW blurred.JPG
Open mpoe OW blurred.JPG
On the left side we have the ISP/ External Wiring side of the MPoE. On the right side we have the Customer/ Internal Wiring side of the MPoE.

Drop Wire/ Outside Wiring

This is the actual line being delivered to your home. On the day of the drop, continuity is confirmed and the proper pair is tied down to the binding posts on the external side of the MPoE.

Here we see the drop (red arrow) on the ISP side of the MPoE, and a blue/ blue-white wire pair which it carries in tied down on a set of binding posts (yellow arrows).

Internal Wiring

This is the wiring that will be connected at the jack(s) within your home on one end and at the internal binding posts in the MPoE on the other. There may be just a single, or multiple runs of internal wiring stemming from the MPoE.

In this MPoE we have 2 runs of IW: the first denoted by the orange arrow, and the second by the purple arrow. Note that each run of wiring may have a single pair of wires, or multiple pairs.

  • If you are unsure which pair(s) are connected at your telephone jack, you may want to open it to find out.
From the inside of this jack we can see that 2 pairs are connected: a blue/ blue-white pair (blue arrow), and a green/ green-white pair (green arrow).

Binding Posts

You will find binding posts both on the internal and external side of the MPoE. Binding posts will always come in pairs. One pair of binding posts and wires constitutes as a single line of service. For example, in an X2 dual line service, you would be tying down 2 wire pairs (4 wires) on 2 different sets of binding posts.

Here we have 3 sets of binding posts on the ISP side of the MPoE. Within the blue ring is the first set, within the orange ring is the second set, and within purple is the third.


These are the wires that carry the connection between the external binding posts and the binding posts on the internal side.

Noted here are a red and green wire pair stemming from module #1 (green arrow) and are tied down to the first set of binding posts (yellow arrows) on the ISP side of the MPoE.

  • Note that it is important to determine which binding posts on the internal wiring side have jumpers connected to them as this is where you'll be tying down your wire pairs.
A top view of module #1. From this angle you can see that the first set (red arrows) of binding posts is where the jumpers are connected, and that the second set (blue arrows) is not connected to anything so will not be useful for tying down IW

Test Jack

If your MPoE has a test jack, it an be used to confirm dial tone and sync without connecting any internal wiring. If phone or sync issues are present, it can also be effective to try using the test jack to determine if the problem is on the inside or outside wiring.

  • Unplug the test jack and plug in your own phone or modem to test for dial tone and sync.
  • If you're using a phone, dial 933# to confirm the phone line to connected to is your own.
This test jack is in the open position (i.e. the RJ-11 connector has been pulled out, which in turn lifts the IW from the circuit)


The module is an encasement for the binding posts, jumpers and sometimes a test jack. Modules are only present on the internal side of the MPoE. Most modules tend to have covers that may need to be removed before you can see the binding posts.

Outlined in red is 1 of 3 modules on the IW side of this MPoE

Completing the Cross Connect

  1. Identify which wire pair(s) are connected to the jack you would like to activate. See Internal Wiring above if you need help doing so.
  2. Find which external binding post the outside wiring is tied to.
  3. Follow the jumpers from the external binding posts to the proper module(s).
  4. Tie down the internal pair to the proper module(s). You will need to loosen the binding post with a screwdriver (one turn should do) and wrap an exposed portion of the internal wiring around it. Tighten back down when finished. Polarity and does not matter and either wire in the pair can be tied down to either binding post.
The first wire of the pair being tied down. The second wire of the pair being tied down.
5. Trim excess wiring. Any excess wiring should be trimmed down to minimize the potential for contact with other metals/objects which in turn can hinder the performance of the line.
Excess wiring which protrudes after tying down a wire to a bind post (noted by red arrow) should be trimmed down to a minimum (noted by green arrow) to ensure that the slack doesn't make contact with anything which might hinder the performance of the line.

6. Test the connection at the jack within the home. The fastest/ easiest way to do so is to plug in a phone to check for the presence of dial tone. If dial tone is present congratulations, you've successfully completed the cross connect!

Additional Resources

Here is a link to a video we created that goes over the process, which may also be useful: