I have a couple week old '18 C63s coupe...not to digress but this car is the ****. I'm about 100 miles away from the 1,000 mile break in and I've been trying to go easy on it and keep her below 4k RPM....what a tease.

Ok, back to the point of this post...last night I hardwired the front dash cam from my old M4 (which was a breeze to hookup in that car since there's a 12v socket under the passenger foot well). No biggie on tapping a fuse in the Merc though since my weekend car is a '67 Bronco, so I'm used to wiring issues, let alone ripping the whole engine apart. Anyhoo...the German fuse diagram posted somewhere on here is no help at all. FYI, I just run a front dash cam for when I'm driving so I don't have an external battery. That said, I was trying to tap what I though was the glove box light (i.e., I wanted an intermittent fuse), but the "C-Klasse" German diagram obviously doesn't apply to my car. The pic below is where I plugged in my add-a-fuse, then grounded it to the metal bolts in the frame and ran the wires up through the trim.




The dash cam powered up fine so I figured all was good, and went inside to drink a beer. I came back about 20 minutes later and saw the dash cam was still powered up though, so obviously this fuse is constant, which I don't want since I don't have (and don't want to deal with installing) a Power Magic Pro box. I just want a basic dash cam that records when the car is on and shuts off when the car's off. So simple question....what freaking fuse do I tap into?

Second question. I'm also putting in my Uniden R3 from my M4, which I had powered through a Mirror Tap to an intermittent mirror light (maybe the compass?) in that car....where do I plug those terminals into in the Merc from the mirror/map light area if anyone knows?

Thanks folks!

 

you can use a voltage circuit tester and test the fuses when your car is off to check which fuses are on all the time or only on when the car is on.

 

As for me, I do have a power magic pro box so I keep it on at all times. I've already had to deal with some vandalism to my car and I'm not going to let that happen again!

 

Thanks. Yeah I have a voltage tester, but I also don't want to tap into a fuse for anything critical, which is why I thought the fuse I tapped was for the analog clock based on this fuse map, which I assumed wouldn't be constant: https://mbworld.org/forums/attachments/c-class-w205/307530d1428728290-fuse-map-fusemap.pdf

I've got a blank in slot at 210, which I'm assuming is for a heated steering wheel from the map, since my wheel isn't heated. I'll give that one a shot when I get home later.

 

 

all passenger side fuse are constant on, allegedly. so you are on the wrong side to begin with. FWIW, i find that the passenger side power flickers (not exactly constant) when car changes mode.

 

Search W205-Sedan & Coupe forums for dash cam/radar detector install info regarding fuse taps, etc.