An Indispensable Tool: MB Star SD Connect

And a demonstration of how I've already used it on Evonne, my current turbodiesel project.

In today’s video, I show how the MB Star SDconnect can be used to perform coding changes on a Mercedes vehicle. I’ve used mine this way in the past to deal with things like airbag sensors that didn’t work, changing AirMatic suspension to coil springs, and (as in this case) shutting off the SOS telematics system. These systems can also be used to access CAN bus devices throughout the vehicle in the fashion that only a manufacturer-specific tool can, and really give a lot more utility than just another OBD2 reader might.

I got into working on Mercedes diesels a number of years ago, after working on my Diesel Suburban project and VW TDIs for a number of years, I stumbled across an inexpensive R320 CDI and started down the Mercedes Turbodiesel rabbit hole.

I found out that VW (and Audi) parts were surprisingly expensive. When I got into the Mercedes machines, I was surprised to find out that the parts weren’t any more expensive than the VW parts. Plus, I found out that the Mercedes machines didn’t require as much maintenance or attention in general.

With the VWs I needed a VAG-COM to really be functional and take care of things that would otherwise be very difficult for an amateur to take care of. Likewise, for Mercedes, an amateur mechanic really needs to consider purchasing a MB Star SD Connect. This is essentially the dealer tool, consisting of a multiplexer, cables, and a laptop computer.

Before you start pricing full-up multi-thousand-dollar dealer tools, keep your purpose in mind. If you are like me you are an amateur mechanic who does this for fun and you aren’t opening up a garage to work on cars for money. If you are, then you should really make the investment. For me, it made sense to go purchase a Chinese-built knockoff of the SDconnect. I purchased mine from AliExpress a number of years ago.

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Some tips on buying these on a place like AliExpress:

  • Look for a seller who has sold quite a number of these. 50 or 100+, and with plenty of ratings to check.

  • Ensure that their seller ratings are very good, I’ll generally look for somebody with 4.5 or more stars out of five.

  • Try to buy a full system that is ready-to-go, in order to avoid headaches. Ensure that you are getting at least the OBD cable, in addition to the multiplexer, and a computer that has all the software loaded.

I bought a laptop, a pre-loaded hard drive, and a multiplexer from separate sellers. I also realized I needed a set of cables and had to make another order in order to get those. Once I had it all, I got the hard drive seller to help me set up the connection between the computer and the multiplexer.

In the end, I didn’t save any money versus the full kit, and if a full kit doesn’t work you have a single contact to reach out to in order to get things working. If my setup didn’t work, the hard drive seller could have pointed at the multiplexer who might, in turn, point at the cables or the computer as the issue.

If I was buying one again today, I’d give, I haven’t purchased anything from them, but they have a lot of useful information on their site and their pricing is competitive.

In today’s video I show how to get rid of the notoriously annoying SOS telematics error by recoding that feature to “not present.” Here’s where to find the setting:

  • Control Units

  • Body

  • Central Gateway (CGW)

  • Control Unit Adaptations

  • Read coding and change if necessary

  • Telecommunications

  • Telematics Service “Tele Aid”


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