jimbo01 0 Report post Posted August 23, 2010 (edited) As part of my upgrade I did the research to idnetify which wires to cut into (for standard business radio) Left front + yellow/red Left front - yellow/brown Right front + blue/red Right front - blue/brown Left rear + yellow/violet Left rear - yellow/gray Right rear + blue/violet Right rear - blue/gray The 2 charater alphabetical codes for the BMW wiring colours are as follows (and not what what i expected) BL = Blue BR = Brown GE = Yellow GR = Gray GN = Green RT = Red SW = Black WS = White VI = Violet Edited August 24, 2010 by jimbo Quote Share this post Link to post Share on other sites