Hello,

Thanks for your help in advance.
I looking to run two cables from the battery into the cab of my c200.

Upon a quick search i discovered that there are pre drilled oem holes that apparently run into the cab.

I wanted some solid info regarding these holes. Please see image.

Which plugs do i remove? Theres black plastic discs which look like the back of a plug and then upbove, you see the soft rubber semi oval shaped plug ends? What is what. Do they lead to diff destinations.
Where to they lead?
What else must be removed so the cable with flow freely to the cab when trying to route it?
Are these infact pre drilled oem holes or was the inital info i got false?

Just wanted more confirms before i poke around.

 

Bump

 

I only pulled one of the round plugs out ... I don't remember others.

 

Thanks. Ive decieded to post back information just incase it helps someone in the future.

So from what ive gathered, the rubber plugs are rubber grommets however you simply cut the end piece off to form the grommet. Mb technician confirmed this.

So in the pic, you can see two larger red cables below the gromets in pre drilled oem hole tubes.

My guess is each hole is a tube, some pluged with grommets and the rest just pluged with plastic to save cost.

So where does the tubbing go?
On the passenger side, slide the seat back, remove the feet mat to reveal the carpet. The carpet runs all the way up till you hit plastic. The carpet is not like house carpet, it is glued firmly to a plastic backing. Dont be affraid to remove the carpet.

Take your fingers and work them into where the carpet meets the plastic. Youll soon see that it is easily removeable by hand. Fold it back, then simply pop off the black foam board thats behind it.
Put the board somewhere where you wont lean on it!

Youll be staring at a metal plate now, with various cut shape holes, notice those two red cables up the very top right corner.

Thats where your cables will come out off. Again, im not 100% sure all grommets lead here. Will post back once ive completed the job but from the numerous posts and convo i had with mb tech im pretty sure.

How to feed the cable through?
I bought 1 meter of metal wire about 5 mm. Strong like a coat hanger but flexible like string. Bit of duct tap on the end so you dont scrap. Once you found the hole you want, run a strong string cord through like para cord or dynemma. Twist around your cable, tape and pull through.

Remember to seal up the grommet as these tubes run into wiring as youll see behind that metal plate. So either silcion or something.

Ps. Seems like youll have to pull the battery out aswell if you really wana ensure you get a seal on the grommets/holes.

Remember to never disconnect your merc from a 12v battery source. Could blow or reset your electronics. Also when hooking up your auxiliary battery, make sure you connect in parallel NOT series. Series will produce 24volts. You want parallel.

Other info :

Wire the fuse on the positive cable near the battery.

Get the right gauge cable to avoid voltage drop and thermo runaway and make as short as possible. Also, is better to go thicker in guage then shorter in that spectrum.

youll need to determime how many amps youll be pulling aswell.

Sorry if thats a heap of info, just thought id save you searching around.


Enjoy your custom 12v socket.

Ps: from what ive heard, alot of mercs have these oem pre drilled tubes so its not just the w203.

If your car has the same holes grommets strip behind the battery, and when pulling the carpet you see the cables there.

More thank likey you have this feature.


Cheers.