Ok, tonight was my first night driving with navi on. Couldn't get over how BRIGHT the screen was. Annoyingly bright. So I looked to see if it had a night mode. The navi was in auto mode.. I had to manually set it to night mode. What's with this? Does the base PiP head unit not auto detect night and day map scheme? .... am I doing something wrong? Shouldn't it switch automatically?
Maybe your instrument panel light control is set to all the way bright. This is when the control is dialed up past the point where it will click. If it is, the instrument panel and navigation display don't dim at night. See the Owner's Manual pg. 260 for a picture.
My 2012 Plug In has 3 settings for brightness, Auto, Night & Day. On the map menu. Mine was set on Auto with the IP lights full on. I checked and it was on Auto so I set it to Day and it's much more to my liking.