I don't seen any *visual* differences between day or night.

night mode makes the navi backround black. you have to turn that setting to automatic and have your illumination wire hooked up. then turn on your lights

If you don't see any visual differences, you may have 1 of 2 problems that I see:

1) The night/day setting is not set to automatic.

2) The IL wire (illumination) is not hooked up correctly

I had this issue after my install and the IL wire was not hooked up. Stupid BestBuy guy who had done the wiring had just capped the wire instead of connecting it through the harness (he also didn't finish the install since they couldn't figure out how to mount the GPS externally b/c the wire was thicker than the Sirius cables they normally deal with. I then installed the thing myself).

Hit

MENU - SETTINGS - HARDWARE - CONNECTION STATUS

And look at the ILLUMINATION line. Turn the lights on and off. If it changes it will tell you what mode you are in, if it's always off, then you are in day mode.

If you don't see any visual differences, you may have 1 of 2 problems that I see:

 

1) The night/day setting is not set to automatic.

2) The IL wire (illumination) is not hooked up correctly

 

 

I had this issue after my install and the IL wire was not hooked up. Stupid BestBuy guy who had done the wiring had just capped the wire instead of connecting it through the harness (he also didn't finish the install since they couldn't figure out how to mount the GPS externally b/c the wire was thicker than the Sirius cables they normally deal with. I then installed the thing myself).

I got my Z1 installed at Bestbuy as well. They also did not connect illumination wire. Lets hope that they just capped it and not cut it off cause if they did that I am going to be PIST!!