I have an alpine w202 unit in my car. The dimmer is set to auto and works great. When i set it to on it the screen stays dim even if the lights are off. I dont mind as i always have the setting to auto. I had a look at the wiring and therr is no dimmer wire which my previous head unit had. I'm thinking of getting the n099p sat nav unit which has a night mode. My question is will i have to go into the settings to activate the night mode in sat nav manually or will there be a dimmer lead with the sat nav unit? Or will it automatically go to night mode in the auto dimmer setting?