What converters would I need to add an amp/sub to my non-ML is200t? Would I have to get under the dash? I have an audio buddy that builds/customizes audio systems. I just need to know how complicated and what I will need first. Car does have Navi. Will be adding a JL audio package to the car. Advice/info would be greatly appreciated. And yes I've searched and didn't find a straight forward answer.

 

I am interested in this as well.

 

You don't have to go into the dash. You handle the connections at the factory amp, which is located in the passenger side corner of the trunk, underneath the first aid kit. You will need a hi-lo converter, and an amp kit, and miscellaneous things such as subwoofer wiring, zip ties, wire taps etc, all of which your installer should have on hand.

I used the Audiocontrol LC2-I for the hi-low conversion. It did the job, but i do not recommend using the signal sensing (GTO) turn on feature that it has. I had a deafening humming noise from the sub when I turned the car off, and apparently it was due to the timing in which the device processed the shutoff signal to my aftermarket amp. I ran a remote wire to my aftermarket amp from the fuse box in the front, and the problem was resolved immediately.

As far as what wires to tap into, your installer should have this information. But this is a diagram that I found on this forum, to give you an idea:

 

To bad theres no pin out for the ones with the ML system

 

This info is on the forums if you searched

 

Thank you very much

 

You're welcome. Keep me posted on how it turns out. I'm a huge audio fan, so always good to read about another successful install!

 

Subwoofer is the +- gray / blue wires pins 6 & 21 on the 30 pin plug at the factory amp which was posted earlier. Cut those wires and run them to high level inputs on the after market sub amp.
I've measured the factory sub, doors and dash signals. The sub appear to have a steep low-pass crossover at 100Hz but plenty high enough for what most people would need.
pins 14, 15, 29, 30 posted earlier are rear doors. Both the front and rear door speakers appear to be high-pass crossed at 60Hz. So anything below 60Hz is cut.

 

So I tapped the corresponding rear right and rear left wires pre factory amp into my scoche line output converter, grounded it, tapped my amp 12v power to also power the output converter. Turned everything on, sub works, but rear speakers have no response. Any ideas?

 

Do you got pictures of what you did? Which model line out converter did you get? They typical do not need to be powered to work

 

im about to put a CRAZY system in this 2017 is200t i got at the end of 2023. thanks for your post. saved me a buuuuunch of time. lmk if you later learned anything else cool/interesting about the audio or whatever else in this car. will post pics and whatnot later.