PiMost for Mercedes


first of thank you for your amazing work. I was always annoyed at the lack of support for MOST Bus. Your PiMost is exactly what i have been looking for.

As I have seen, nobody has tried to use it with a Mercedes yet. Since I have just bought a W211 E-Class with the Command system, I want to try to modernize it a bit and add bluetooth audio with steering wheel control. Since the Headunit and CD Changer only have power in and MOST, I need to tap into it.

As I understand streaming audio is part of the specification and should be exactly the same on all makes and models, correct? That would make it way easier to reverse engineer.

Also do you know how the can-bus is being transmitted over MOST? I haven’t found anything in that regard.

I’m waiting for the 12 Volt version of the PiMost so its easier to integrate into the car. Any ideas how long till it will be available (annoying question, i know. Sorry :D)

I already did some car hacking on BMW’s when I still had one and MOST was always annoying, but at least they had the courtesy to add some normal cables and can-bus directly to their systems.

Anyways, thank you for creating and publishing all the resources!


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Hi, welcome!

There has been a purchase for a mercedes, but unsure how far they have got with testing etc.

Streaming audio is part of the specification, and so far no car has not implemented it in the standard way. I would be suprised if any did, but there’s always a chance!

From my JLR experiments, can is translated in various ways, sometimes it is a copy and paste of the message to MOST, other times it is formatted in a more user friendly way.

An example of this is my parking sensors, on can they are transmitted in 5 bits, so all 8 sensors are 40bits spread accross 5 bytes. But on MOST they are translated to just 1 byte per sensor, so much cleaner!

I think the 12v version may not make it to production, the USB-C version has 5v headers which I power from one of these https://www.amazon.co.uk/dp/B08YXHR5GY?ref=nb_sb_ss_w_as-reorder_k0_1_6&amp=&crid=202EYNB8JXGQ2&amp=&sprefix=12v+to and it works well, with the small volume of these that I sell, it would make everything more expensive to maintain two versions, so I feel it’s best and cheaper just doing the usb-c version.


That’s surprising - what version of Comand is in your car? Mine’s a 2009 r171, which has an NTG 2.5; with that head unit there is a quadlock connector on the back that has the MOST fibres, but also a bunch of other wires including a CAN pair.
(I don’t have my laptop with its 2020-ish copy of WIS nearby, but a w211 should definitely be old enough for the wiring diagrams to be present)


it’s a NTG 1. This version only has Most Bus connected, nothing else. In April of 2008 the NTG 2.5 was put into the W211. Since then the Quadlock was present.