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Msmax · 09-04-2006, 01:55 PM

Hello Bazzle,

Maybe I can explain how this CS7.4 works.

At first in MB all controllers are connected to different pins in the 38pin plug under the bonnet for the pre 2001/2002 cars. Means you can have 38 - (12V) - (GND) = 36 communication channels.

Your PC only has 1 comms channel.

So, the software sends a "pin selection" command to the interface which then selects which pin to "connect" to the PC. After this the PC will send commands for the controller to which it is connected to.

The selection for data to interface or car and interface reset is done using the DTR signal in the RS232 commport.

This also means that you should have bought an multiplexer (MPX) interface which understands the selection commands to be able to read all the different controllers in your car. I do not think that your interface is a MPX model.
It will work if you can connect the data line from the interface to each of the pins in the 38pin socket seperately, depending on what you like to diagnose. Means for ABS connect to pin 6 for KI connect to pin 15 etc. The cable with the RED/BLACK and Yellow plug are used for the W124 and before series for analogue diagnosing. If you manage to make a cable with smaller plugs then you can diagnose the other sytems as explained above.

What you have bought is also known as a K(K)L interface which costs about 50 euro and is very well suitable for diagnosing VAG cars with VAGCOM.

Hope this makes it clear why you can read errors from your motormanagement only. It is connected to pin 4 or 5 (depends on the model).

Pin 1 = GND
Pin 3 = 12V

The ME ONLY stores errors related to the motormanagement.
The ABS controller stores ONLY errors related to the ABS system... etc

Regards, Msmax

PS. Do not go for Scantools if you like to have access to other controllers then the motormanagement system.
This is an OBD2 diagnose tool which is worth the price but will ONLY diagnose the engine system.
If you do use scantools hardware then please check out my OBD2 software package which works fine with Scantools ELM 327 and mOByDic interface at www.obd2spy.com
OBD2 is implemented in west Europe from 2001 for petrol engines and from 2003 for diesel engines.

CS has code to access all other controllers in your car too.

09-04-2006, 01:55 PM	#9 (permalink)
Msmax BenzWorld Junior Member Date registered: May 2004 Posts: 9	Hello Bazzle, Maybe I can explain how this CS7.4 works. At first in MB all controllers are connected to different pins in the 38pin plug under the bonnet for the pre 2001/2002 cars. Means you can have 38 - (12V) - (GND) = 36 communication channels. Your PC only has 1 comms channel. So, the software sends a "pin selection" command to the interface which then selects which pin to "connect" to the PC. After this the PC will send commands for the controller to which it is connected to. The selection for data to interface or car and interface reset is done using the DTR signal in the RS232 commport. This also means that you should have bought an multiplexer (MPX) interface which understands the selection commands to be able to read all the different controllers in your car. I do not think that your interface is a MPX model. It will work if you can connect the data line from the interface to each of the pins in the 38pin socket seperately, depending on what you like to diagnose. Means for ABS connect to pin 6 for KI connect to pin 15 etc. The cable with the RED/BLACK and Yellow plug are used for the W124 and before series for analogue diagnosing. If you manage to make a cable with smaller plugs then you can diagnose the other sytems as explained above. What you have bought is also known as a K(K)L interface which costs about 50 euro and is very well suitable for diagnosing VAG cars with VAGCOM. Hope this makes it clear why you can read errors from your motormanagement only. It is connected to pin 4 or 5 (depends on the model). Pin 1 = GND Pin 3 = 12V The ME ONLY stores errors related to the motormanagement. The ABS controller stores ONLY errors related to the ABS system... etc Regards, Msmax PS. Do not go for Scantools if you like to have access to other controllers then the motormanagement system. This is an OBD2 diagnose tool which is worth the price but will ONLY diagnose the engine system. If you do use scantools hardware then please check out my OBD2 software package which works fine with Scantools ELM 327 and mOByDic interface at www.obd2spy.com OBD2 is implemented in west Europe from 2001 for petrol engines and from 2003 for diesel engines. CS has code to access all other controllers in your car too. Last edited by Msmax : 09-04-2006 at 02:05 PM.