Can someone please tell me where to locate this wire and what color it is?

the wire color is green with black stripe or green with orange stripe, this wire is located at the bottom of the fuse block in a white connector where the wires exit out toward you.

Thank you for your reply. I have been working (over PM's) with SDJ99 for a while now and he has been having trouble finding this wire. I/we really appreciate the wiring diagram, but the resolution is too low to be able to read it.

I had him take the ILL input wire and just touch it to 12V to make sure it goes into "night mode", cause he was saying it wasn't working (the wires he was told to connect to) and when you just touch the ILL input wire to 12V (like battery +) it worked so we know the Z1 is working. He just needs to find the ILL wire.

Any chance this vehicle has a light sensor and he is testing this in the day time and that's why he thinks it's not working?

I don't have any experiance with Lexuses and can't help more than "theory" and where stuff should be connected.

I'm not saying you are wrong with your ILL wire sugestion (I don't even know if he tried this connection yet). He might have read this and tried connecting to the wrong wire. Just thought I would try to help.

After talking with Brachoza again, the Illumination wire is actually located in the factory radio harness. It's the green wire between the red wire and the white wire. Once I tapped into it the Z1 switched to night mode whenever I turned the lights on just like it's supposed to. Much thanks to Brachoza and Ducatiboy for all their help in tracking this down and getting it working.