Stereo Harness Confusion!

[Anno LS]

Hi all, I am a new poster here and am having some trouble with my 2004 LS V6. I’m currently replacing the stereo (not THX nav, but it is the 12 speaker system) but I have a 6 pin harness in the car that has no equivalent in the Crutchfield harness (SWRFD-60L). There are only 2 wires going into the harness, blue/yellow and grey/black. Any idea what this harness is for? Thanks in advance!

 

[joegr]

That connector is labeled 290c. That's the SCP module communications network. That's where the factory radio gets the information needed for speed based volume control and for the retained power (where it doesn't go off till you open the driver's door). The aftermarket radios can't use that information (they don't speak the right language), so there's no reason to have any harness adapter for that connector.

 

[Anno LS]

Thank you so much! I assumed this was the case as a very vague wiring diagram only said “computer datalines”, but I wanted to make sure it wasn’t anything important. Appreciate the help!