woodlander

By the way, the reason I am looking into this isn't for the bass, although I may get into that at some point... I am trying to direct wire my Escort Max - and was juat going to use an add a fuse to the back, but wasn't sure where a good ground was... Looks like I found that, but now am just a bit apprehensive about using the add a fuse!
Any thoughts?
I'd prefer not to vampire tap any wires if I can, which is the reason I'm looking at doing a long run from the trunk to the front in the first place

F3LiX

If you get a solid connection with a fuse at a fuse terminal of the rear SAM I think you'll be fine. As i mentioned, to stick a spade in a hot relay terminal can be dangerous because ya dont know what that circuit is intended for. A fuse terminal is usually getting its juice from the battery to power a relay. So, with the correct connection and protection of the add fuse Id be comfortable with that.

Arrie

If you are pulling wires from the trunk why not use the "cigarette lighter" in the trunk?

robl45

Doing this in the next two weeks with the same box used here. If anyone knows the best location to hit that box or another source of power in the back for a 2011 e63 I'd appreciate it.

woodlander

Thanks Arrie, I have been pondering this as well since I saw your post.

I had the bright orange extension cord going from the trunk to the cabin for a while, which I hated, although it worked, it would come loose every now and again, and looked far from MB quality.

Guess my main reason for wanting to tap a fuse and run small flat wire is for cleanliness and a storong connection, but better route planning and a few zip ties (along with a black wire) could solve all that.

One thing I noted when I had the fuse chart out (which I posted), one lighter is 7.5a, the other is 15a... Will that make any difference?

If I tap a fuse, I'll likely use the sideways 15a in the middle of the trunk board, if that helps you, Rob - any thoughts on that F3lix? (It's the cigarette lighter one, #92) or I could even do the fuse which powers the trunk power port... (#72)

Happy Monday!

DJ Hellfire

ALWAYS install the amp's power directly at the battery with a fuse 18" or less from the battery. NEVER plug power cables into the fuse box like this.

woodlander

Agreed on the amp DJ...
BTW, you from NJ? I grew up in Union and Bergen counties...

Has anyone ever "readded" the second battery in our e350s? Is it possible? How was the original charged, did they leave that stuff in tact? It would be great to have a second power source in the car, as long as something is there to keep it charged...

Jlataille

Simple calculation to make the proper fuse requirement.. divide wattage by 12 volts...and always keep the 18" length or less from the power source. smaller gauge wiring will cause resistance and ultimately melt the insulation causing shorting or arcing against metal. last thing any of us want is to see a benz on fire. the run from the battery to the back isn't too band as there are many easily accessible openings in the firewall and going straight back down the passenger side. also, grounding and power cable should always be the same gauge, but grounding wire never more than 3 feet (estimate) from the amp. more power doesn't mean better sound, nor does more equipment. My previous experience was in some of the better shops in RI and in FL before the military.

Woodlander- if you're referring to adding a second battery, IE audio yellow top, its simple. find the placement for the secondary battery and run your proper gauge wiring from your stock battery and connect as normal. when connecting an amp(s) utilize a capacitor with the designated farad needed for your system so you don't put strain on your charging system, after the second battery and before the amp of course. make sure you fuse the wiring on both ends just as a precautionary measure.

DJ Hellfire

Yup. I'm in hazlet.

Celicasaur

I used this red/grey wire for my switch power. I connected by wire to it and tested the end of my new wire with a multimeter. When the ignition is on, I get 9-10v from it. If I touch the new wire to the remote/switched port on the amp with the multimeter still connected, the voltage drops down to 0 (amp does not power on). Anybody care to explain why this is happening? I tried hot wiring the amp (directly connecting a wire from the power off the amp to the remote/switched port) and the amp/sub powers on just fine. Hmmm...I want to ask for another switchable power source, but why is it showing 0 volts when connected to the amp?

Also, FWIW I used a thicker power cable for the amp as can be seen here. Assuming this is safe enough, right?





I tapped into the green and green/brown wires as explained by the OP but need to buy some phono leads tomorrow to connect properly into the amp for good sound signal.