Decided to play around with my 04 TL and performed the following:

1) Took the carpet out in trunk
2) Pulled out the XM unit using the instructions in https://acurazine.com/forums/3g-tl-audio-bluetooth-electronics-navigation-94/diy-audio-aux-577329/
3) I ended up cutting off the XM connector, assuming that I am never going to use XM (never have in 6 years of ownership) and keep it simple to pull 12v and audio connections from XM connector.
Got the multimeter out and tried to find which one is the power. Here is when the fun starts.

At first, the stereo head unit would not switch to XM anymore.
Then I somehow managed to disable the display completely as well as not have any A/C function. Looked up all the fuses under hood and by the pedals, only 1 7.5Amp fuse is blown for back light.

Requesting help on following:
1) Is there a way to cut out XM and still get the head unit to switch to XM input? I was planning on putting in the Kinivo BTC450 in the trunk.
2) Any suggestions on what is going on with the head unit display?

I do not have Navigation.

Thanks in Advance.

 

wrong section.. this is the 4g.. mods please move.