MBES W211

Hi all, I'm trying to hardwire a dash cam to my 2008 E350 and I need to tap into two fuses on the driver side dash. I need one fuse that's always on and one accessory fuse that's only on when the car is on. Problem is when I use my fuse power tester, all the fuses light up even when the car is turned off. I heard this could be if I just turned my car off/have the door open/etc. so I tried to trick the car into thinking the doors were closed and locked by jamming cardboard into the door latch and locking the doors with my key and waiting a while but nothing changed. Has someone done this on their W211 and can help me with which fuses are accessory fuses or think of a better way to trick the car into shutting down? Any help would be appreciated. Thanks

tjts1

On my 04, I disassembled the overhead consider and found a key triggered 12v wire that I spliced into to power my dash cam. Sorry I don't remember exactly what that wire powered (maybe the SOS button?) but it works for me. If you're handy with a multimeter I guarantee you'll find a power source up there.

Good luck.

MBES W211

I'll have to take a look at that and give it a shot. Thanks!

E55Greasemonkey

You can also run the wire to the back of the ashtray and tap into the cigarette lighter wiring.

rapidoxidation

The ashtray can be either always on or switched on according to the position of the ashtray fuse in the fuse block under the hood.

ps2cho

This is how I hardwired mine - You can pull the connector out of hte back of the cigarette lighter, then just shove the new wire in/wrap it around and close it back up. No issues for a year now.

MBES W211

Thanks for all the tips. I finally got around to installing it this past weekend and had no issues. Ended up just tapping straight into the cigarette lighter fuse in the engine bay. The wire was just barely long enough to get to the fuse box in both the engine bay and the driver side dash and I ran the wire in through the gaps in the hood, front fender body panel, and the front driver door. Also had to chip the side of the fuse box cover in the engine bay to allow room for the wire to go through but hopefully this won't lead to any future issues. Thanks again!

aobnitas

I tapped 12V from the back of the center console's cigarette lighter. Easy access from left side fuse compartment.