Been trying to solve this for months...I have an 04 TSX with Nav. Decided I wanted lights on my steering wheel controls (Stereo and cruise controls) so i bought everything needed on ebay. First i must say the stereo and cruise control functions work JUST FINE.

So I used the 06 steering wheel harness because i essentially had to, the cruise and radio control wires didn't unplug on each unit like the 04 did. The 06 harness had a green 5 wire plug (only had 4 wires) that plugged into the voice controls and the 04 has a 4 wire plug, so of course i had to swap the 4 wire plug over to the 06 harness. This is where i must have crossed some wires up.

Does anybody have a wire diagram for an 04 TSX steering wheel harness? Because after months of searching i cannot find one....The 4 wires going to the voice controls are GREEN, RED W/ BLACK STRIPE, BROWN, GREEN W/ ORANGE STRIPE. Thanks for the help!

Here are some pics of the harness TSX Wire Harness - Album on Imgur

 

From the 04 Electrical Troubleshooting Manual.