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Created: 22 Aug 2007

Last Updated: 29 Dec 2007

Version 1.2 28th August 2007

This document describes the Mercedes Star Diagnosis system. In Germany this is known as 'Star Diagnose'. Star Diagnosis is also known as SDS or DAS by Daimler Chrysler, although the acronym DAS is also used for the electronic key system.

It briefly covers the J2534 system that Mercedes make available in the USA for updating and configuring the emissions related systems on Mercedes vehicles

Star Diagnosis (SDS) is a complex system that consists of various parts

  1. Ruggedised Laptop, or Laptop in special cradle
  2. Multiplexer
  3. Cables
  4. DAS Software (The 'Star Diagnosis' program)
  5. Optional MT measurement system.
  6. Optional WIS (workshop information system) software

Over time it has been available in various forms, each new release containing faster/better hardware.

The two ranges of Star Diagnosis are known as the 'Basic' range and the 'Compact' range.

The Star Diagnosis Basic range has essentially a much lower specification ruggedised PC, and thus is not sold with the ability to interface to the MT system to have WIS, or to use the latest wireless multiplexer.

The current 'Star Diagnosis Basic' system is known as the 'Star Diagnosis Basic2', and the current Star Diagnosis Compact system is the Star Diagnosis Compact 3W system.

Hardware details: -

Basic 1   - Ruggedised PC made by IME Actia with Celeron 400Mhz processor, 128MB memory and 20GB har drive with Windows NT 4.

Star Diagnosis Basic system

Basic 2 -   Ruggedised PC made by IME Actia with Mobile Celeron-M 600Mhz processor, approx 512Mb memory and 60GB hard drive, 10.4" XGA screen, with Windows XP. It has USB 2 serial ports, the pen is tied to the system and its a blue colour as oppose to the grey Basic 1 system

Star Diagnosis Basic 2 picture

Compact 1 - IBM laptop PC in special metal cradle

Compact 2 - IBM  T20 or T23 PC, in special metal cradle. Windows NT

Picture of Compact 2, out of its docking station with extra power adapter.

Star Diagnosis Compact 3 picture

Compact 2 Station MT - A compact 2 with MT measurement system (see later) and printer in a nice workshop trolley.

Compact 3 - Tablet PC with 15" XGA touchscreen, With Windows XP, 1.1Ghz Pentium M, 512MB Ram, 60Gb hard drive

Star Diagnosis Compact 3 picture

Compact 3W - Same as Compact 3, but with integegrated Wireless LAN, possibly with larger disk and more memory.

The latest system brochuers are available from click on 'MB Workshop Systems' and then 'SDS'

Multiplexer Details

The multiplexer is the interface between  the PC and the car's diagnostic port. The current multiplexer connects to the PC with a cable and is made by I+ME Actia and is called the Part D3 multiplexer. It then connects to old and new Mercedes models using different cables.

Picture of Part D multiplexer.

Star Diagnosis Part D multiplexer

 The Part D multiplexers have serial numbers in them, and if the DAS software detects a stolen/unlicenced one, apparently it locks them out, possibly for good (possibly by flashing duff software into them).

Picture of the multiplexer connector on a SD Compact 2 cradle

Daimler Chrysler are shortly releasing a wireless multiplexer called 'SD Connect' - it will connect to the PC wirelessly, and only to vehicles with the 16 pin OBD-II port. (anything after, but not including the W210 E class / W208 CLK / W202 C)

Picture of SD Connect wireless multiplexer

Star Diagnosis SD Connect wireless multiplexer picture

Star Diagnosis will support a number of other multiplexers, included is the I+ME Actia Part-X multiplexer, although absolutely no information is available on how that works or how to make a normal Star Diagnosis system connect to them. There is also a Part-Y multiplexer that is also apparently used within DC research / factory environment.

Details of the I+ME Actia Part-X can be found at I+ME Website

Part X Multiplexer picture

Star Diagnosis Part X multiplexer

Before the Part D3 multiplexer there were Part A, Part B, Part C and other Part D multiplexers with different functionality - I have never seen them

If you have any information on these or the Part-X or Part-Y i'd be very interested!

MT Measurement System

The MT measuement system is basically a re-packaged Hermann HMS-990 digital oscilloscope. The latest versions connect to the Compact 3 via USB. In the Compact 2, a PCMCIA card was supplied that plugged into the docking staion.

There are litterally hundres of different connectors that connect the HMS990 to the vehicle, the MB brochure for MT cables is here. Note that prices are rather out of date.


Various cables are needed for the Part D multiplexer.

  1. PC to Multiplexer - available in various lengths
  2. Multiplexer to OBD-II
  3. Muliplexer to 38 pin port
  4. Multiplexer to 4 wire
  5. Multiplexer to truck connector

Picture of PC to Multiplexer cable

Star Diagnosis MUX cable

Picture of 16 pin OBD-II Cable

Star Diagnosis 16 pin OBD-II Cable picture

Picture of 38 pin older vehicle cable

Star Diagnosis 38 pin diagnostic cable for W202, W208, W210

Part Numbers

The part numbers below often have to be prefixed with Z to order them - these are European part numbers, and sometimes US part numbers differ for the same parts)


    6511 3500 99    Compact 2 Docking Station
    6511 3450 99    Compact 2 (IBM T2x) battery
    6511 3715 99    Basic/Basic 2 Battery
    6511 3720 99    Basic/Basic 2 Charger
    6511 3710 99    Touchscreen pen (x5) for Basic
    6511 6103 99    Battery for Compact 3 / W
    6511 6105 99    Touchscreen pen (x5) for Compact 3 / W (US part nr 965 589 37 10 00)
    6511 6104 99    Charger for Compact 3/W
    6511 6112 99    Power supply unit for Compact 3/W
    6511 6116 99   Compact 3/W protective cover


    6511 1002 99   D3 multiplexer - there are other part numbers also


    6511 1106 99   5M Cable between PC and multiplexer (US part 963 589 11 06 00)
    6511 1111 99   10M version of above
    6511 1121 99    20M version of above
    6511 1200 99    4 pin vehicle cable (US Part 963 589 12 00 00)
    6511 1220 99    14 pin truck cable
    6511 1240 99    16 pin OBD-II cable (most new cars) (US Part 963 589 12 40 00)
    6511 1260 99    38 pin older passenger car cable (US Part 963 589 12 60 00)
    6511 1280 99    Mitsubishi Canter cable
    6511 1577 99   SDS Test/Car Charging cable


    6511 1650 99   Cushion to turn airbag off when SDS on front passenger seat. (US Part 963 589  16 50 00)

Picture of SDS Test/Car charging cable, used to charge the Basic/Compact units from a car and for testing the diagnostic port on the system.

Star Diagnosis charging & Test cable


Older Diagnostic Systems

Before Star Diagnosis, Mercedes dealers used to use something called 'The HHT' or Hand-Held-Tester. There is a software version of this built into Star Diagnosis for talking to older control units in various cars (such as ABS).

J2534 Diagnostic System

In the USA legislation was passed about 3 years ago forcing automotive manafactures to make systems available for sensible cost that could re-program and configure emissions related control systems.

In order to keep costs sensible, a standard called SAE J1962 was created by the SAE which defined a software interface to a generic multiplexer to connect a normal laptop to all recent (US) vehicles. This included facilities to 'flash' (replace the program) running in the control units that affect emission (such as engine control and gear box control). The interface standard is commonly known as 'PassThru'.

All major manafacturers then released software for a relatively low charge to run on a PC that would then talk to the car.

The Mercedes system is called, rather blandly, J2534 and will only program the emissions related units. It is in fact a cut down Star Diagnosis systems, and informations and manuals are available on the Mercedes startekinfo website, under MB Workshop Resources and then J2534. If you look at the user manual there, you will find the screenshots look just like the full Star Diagnosis system.

There are two manafacturers of J2534 interfaces that I have found, they are I+ME Actia PassThru website and DrewTech.

Buying Star Diagnosis

Many dealers will let you order the cables using part numbers above. You can not order the actual Star Diagnosis machines or Multiplexers from a dealer.

Because of European and US competition rules, all vehicle manafacturers must now make diagnosis tools available to any workshop - so you can buy the systems, but they are far from cheap.

If you are in the USA, you can purchase systems via

If you are in Europe, you can order systems via Daimler Chrysler Workshop AfterSales.

You can, of course, purchase a number of cloned multipexers and other Star Diagnosis equipment from eBay. Here is an eBay UK search that will find most of them, and Here is an eBay USA link that is good for outside Europe.

Further Information

You can download the German HMS 990 (MT) brocuhure here.

The current(ish) system brochures (Compact 3 and Basic 2) in English are available from click on 'MB Workshop Systems' and then 'SDS'

Here is a link to the now superceeded English  Compact 3 brochure

Here is a link to the latest English Compact 3W brochure

If you found this information useful, please support the site by making a donation via Paypal. Any amount at all helps me improve the information on the site.

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