Dash Cam install
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Joined: Nov 2015
Posts: 1,456
Likes: 140
From: Westcoast/Interior
02w163ML500 / 97w210E50AMG / 99w202C230k / 95w124500e-wip
Answer before you move. 
Check your lighter in the centre console tray, if this w166 model has one (not familiar with this however, all models seem to have it still or an additional accessory plug (which may or may not be hot).
Most plugs are accessories meaning they only activate when the car is running. Tap into the lines from behind the centre console by adding a female cigarette oulet plug that your dash cam can plug into and tuck everything under your foot passenger dash area.(for a clean invisible install - pretty easy to do). If the accessory is always hot, then add a rocker switch and tap into the line of the female cigarette outlet plug. Then you can turn off manually or leave it on (for a few hours in parking mode state, if you like - drain on the battery is not critical) or add a backup battery pak if you like in a similar fashion.
W163 has an hot accessory plug on the PS lower foot well so we have the option of tapping into that and adding the toggle switch to manually overide the dashcam and still maintain the hot oem accessory plug.
Alternatively, you can tap into the dashboard fuse box accessory fuse.
Check your lighter in the centre console tray, if this w166 model has one (not familiar with this however, all models seem to have it still or an additional accessory plug (which may or may not be hot).
Most plugs are accessories meaning they only activate when the car is running. Tap into the lines from behind the centre console by adding a female cigarette oulet plug that your dash cam can plug into and tuck everything under your foot passenger dash area.(for a clean invisible install - pretty easy to do). If the accessory is always hot, then add a rocker switch and tap into the line of the female cigarette outlet plug. Then you can turn off manually or leave it on (for a few hours in parking mode state, if you like - drain on the battery is not critical) or add a backup battery pak if you like in a similar fashion.
W163 has an hot accessory plug on the PS lower foot well so we have the option of tapping into that and adding the toggle switch to manually overide the dashcam and still maintain the hot oem accessory plug.
Alternatively, you can tap into the dashboard fuse box accessory fuse.
