The picture below shows a standard BT line cord with the wire colours shown.  All the conversions on this site use this convention.

The cord used is a light grey flat type, that has a ridge in the middle of one flat (the ridge is on the rear of the cable shown in the picture).  This allows identification at both ends.  It is now possible to work out, by using the picture below, which wires on the non BT cord relate to wire colours within the conversion pages.  It is usually possible to see the colours of the wires at the plug end.  Look for the colours just before the gold connectors on the plug.  The plug normally only has 4 connectors and the wires are slightly offset.  As the cable is flat there should be no problem in identifying the wires.

The information below shows the wiring colours of a typical non BT line cord against a standard BT line cord.  Other colours may be found but you see how they line up by referring to the picture above.

Non BT cord BT cord
Black White
Red Green
Green Blue
Yellow Red


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Last revised: August 23, 2023