MooflesThaCat

Hey guys,

I'm going to add a sub that I had from my previous car into my 06 c230 this weekend so of course MBWorld would be my first stop. I searched for a few days on this and found a lot of threads, but the portion for running the power to the battery is what is eluding me. I did see one install where the poster recommended removing the plate underneath the glove box, where I can find four holes that go through the side wall. My only problem is that I looked at the hole and there's now way 4 gauge wiring is fitting through there.

I'm running a single 10" JL W3v3-4 and I really don't feel comfortable running 8 gauge wiring to that.

I also saw another post where the poster ran the power to the stock amp under the seat and tapped that for power, but that doesn't sound too safe either.

My question is, to those who have added subs with 4 gauge wiring... what's the safest and easiest way to get the 4 gauge wiring through the firewall.

Thanks!

MIKESV8

drill a hole and use a grommet.

efzauner

I have a huge install in my C240. happy to share. Yes 4 gauge fits thru the grommets.

here are some pics. Just attach the cable to the battery post connection. I tried to connect it to the fuse distribution block by the battery. No can do. The pic of the amp tray is old. I have 3 amps now on 2 decks with a JBL MS8.

SeaCoupe

I don't see how you fit 4 gauge through the stock grommet undearneathe the dash. I cut my stock 4 gauge by the passenger seat and added a distribution block and then wired in my power leads.
How much wattage are. You running? 8 gauge should be sufficient for a single amp.

hahaitzmickey

sweeeet! did you build that tray yourself?

efzauner

yes of course. the sub fires up thru the existing sub mounting holes. The tray is hung via 4 bolts installed from the top. Heluva job to remove the rear deck to do this.

Right now I am running a 600 watt Pioneer PRS sub amp driving the DLS 10 inch sub. a 2x300 watt PRS amp for the DLS Nobelium mids, and 4x 75 watts for the DLS Tweets tweets and rears. awesome stuff. The C Class is so very quiet inside and the doors dont rattle at all
I also opened up the audio unit and solderd RCA outs to the pc board right after the DSP/DAC outputs.

efzauner

Yes 4 gauge fits I have it. the grommets are quite flexible. Use some lube. I used dishwashing detergent.. but hey. KY would work too!

Do I need to take a picture to prove it?

Hogger

The 4 gauge does fit, but it's a REAL PAIN(at least it was for me). You have to push, pull, yank, do whatever to remove the plug in the firewall panel. Really awkward, but it can be done.

JDM_love

Any tips on removing the black plug to feed the wire through?

efzauner

jees dunno...of the entire install... the plug was not a big deal... plyers?
its been a while

JDM_love

So far I have everything wired up for my subs, just need to get the wire to the battery. The plug is whats stopping me

efzauner

try spraying with a bit of silcone.. twisting.. then pulling out. Man you gotta try something. it was not that difficult

JDM_love

Yeah I'll try that today. Last night it got really rainy so just gave up since I have no garage. Will try today

phister

I drilled my own hole to run my wire through. I put a rubber grommet to protect the wire.

JDM_love

Yeah I ended up drilling my own hole too. Now Everyrhings ready, just have to plug in my new headunit

phister

Just remember the acc and constant power are switched

JDM_love

I had that part understood from the manual my wiring harness came with, what I didn't know was I had to connect power from somewhere like the cigarette lighter. Anyways, completely finished with the headunit installation and subs

Moviela

I know this thread is more than a year old, but let me see if I can save everyone a little time.

To install a sub amp in the rear you do not need to run a wire from the battery through the fire wall under the carpet to the trunk. There is no commercial 12 volt amp that can consume the current supplied by an AWG 4 wire.

The factory runs an AWG 8 wire from the battery to the fuse block in the rear that is properly protected. I cringe when installers run a wire from the battery terminal directly to an amplifier. They have no experience with wire or circuit protection, and it make the car a prime candidate for a car-be-que on Interstate 10.

The terminals on the amps and the wire terminals commonly used cannot use the ampacity of an AWG 4 wire. Your hearing cannot stand the SPL produced by a "1,200 watt" amp. Thankfully the ratings in automotive aftermarket sound equipment are more inflated than mpg figures on a window sticker.

You can tap the power in the back, properly protect the wiring, and still have enough hip-hop thump to annoy drivers four cars back.

jkowtko

This is what I was hoping to hear ... hate to mess with a well-packaged set of wiring, especially when there are so many taps off the positive battery terminal already. So if there is a way to use the power supply to the rear SAM without affecting the operation of the SAM, I'm interested.

Fyi the 12v wire gauge charts found online aren't very consistent. The amperage ratings of 8AWGwire at 10' range from 30A-150A in these examples:

http://www.engineeringtoolbox.com/am...uge-d_730.html
http://www.hifisoundconnection.com/S...e_Speaker-Wire
http://www.rowand.net/Shop/Tech/WireCapacityChart.htm
http://www.offroaders.com/tech/12-vo...gauge-amps.htm

I have a couple of photos of the back of my SAM showing where the 12v power cable enters the unit, and a set of external fuse taps on the bottom (17-19) that are rated at 20A each.

I would venture to say from these photos that the power cable looks more like 4AWG than 8 ... it's a good 1/4" diameter. The fuse ratings on the installed fuses for this SAM (third photo) show a total of around 200A, and adding in the empty slots, closer to 300A. Are you sure this isn't a 4AWG power feed?

So ... if the battery power cable to the rear SAM is a good enough source of power, what is the best way to tap into it?

Do you suggest tapping into the cable itself before the SAM? Or using one of the designated external fuse locations (17-19 in my case) located at the bottom of the SAM? What I don't know is if these external taps run through the SAM logic board or if they are just directly connected to the incoming power cable ... I would only want to use them if the latter were true).

Thanks. John

W211_350WagoN

Hey I know this is a old tread, but I could use a part # for that 17-19 orange fuse tap.
Thanks in advance

jkowtko

Fyi this is a while ago, but shortly after I posted, I went to the local dealership and they couldn't find that part.

Since I ended up running new speaker wire for my Hertz door speakers, I also ended up running an 8AWG wire from the battery down the right side of the car. All is great though. I've had the stereo blasting ever since, 10W3D4 sub in the trunk, and enjoying my music!

W211_350WagoN

Could you look at the one in your car now (the orange one that's alone) in the bottom or top of the Sam and give me it's part # because that spot is open in my Sam.
Great to here everything worked out btw

jkowtko

I just took a look. It's at the bottom of the SAM. There are four spots for these adapters to plug in. However I could not figure out how to pull it out, and didn't want to break it, so unfortunately no part # for now.

Not that it will help, but FYI I found this sub position to have the least amount of bloated resonance in my trunk.



Coincidentally it's directly under the pass-thru vent area so it allows a bit more of the bass to enter the cabin. I plan to build a custom box there to tuck the sub under the ledge and further forward towards the rear seat, and box it in to prevent sound from getting into the rest of the trunk where it will just resonate. And if that goes well I may try upping it to a 12".

W211_350WagoN

Do you see how you press that clip to remove the fuse.... You can remove the orange holder with the same concept, if you look closely you will see a similar clip...

W211_350WagoN

I'm installing a jl 8w7 in a ported box. It sounded great in my w210 in a sealed box and now I have the wagon so it should pump pretty nice.