Hi, new here,

Just purchased and had the AVIC-D3 installed in my trailblazer, was wondering if it was possible to switch from day to a night type of mode so it is not so bright, so I would not have to go in and turn the brightness and contrast down. Thanks

If the illumination wire is hooked up, it should dim when you turn on the headlights.

Try going to the screen settings where you adjust the brightness/dim/etc. Then turn the headlights on and off, you should see the settings switch from day to night. If it doesn't, your dimmer/illumination wire isn't hooked up right.

Opened it up, so is it orange white to orange white? there is an orange white coming off the unit and a orange and then an orange white

So I did hook the unit up to the white white, it works and all, but now there is a buzzing in the head unit. and when i step on the gas its there too.

you hooked up the orange from the unit to the white-white on the harness? thats the problem.