941 MBE ECU Knowledge Base

A wiki page to share knowledge about the 941 MBE ECU.



I'm happy to share knowledge about how to communicate with the 941.

1. Technical Details
2. Versions
3. Current diagnostic software solutions
4. Communication
5. simple python program to query ECU


Asking the ECU for any info takes a few lines of Python.

1. Technical Details

Serial type MBE ECUs Pin Out & Related Wiring Information from SBD Motorsport

2. Versions

[ Juddder]

The version number is an 8 digit code stored in the ECU EPROM and is referred to in the Original ECU Diagnostic software without the 3rd number (presumably to allow wildcard versions)

Known versions that are dumped are shown with the extra number in the brackets and the engine type at the end

1. 9280240 = 928[x]0240 [v8]
2. 9280270 = 928[1]0270 [v8]
3. 9410034 = 941[x]0034 [v8]
4. 9410035 = 941[1]0035 [v8]
5. 9410090 = 941[x]0090 [s6]
6. 9410100 = 941[x]0100 [s6]
7. 9410101 = 941[3]0101 [s6]

I've noted the difference between the AJP V8 and S6 versions by checking how many Injectors the ECU diagnostics software is trying to monitor for each version - Two banks of 1357,2468 for the V8 and 123,456 for the S6

Later ECU software appears to have additional logging such as BuzzLogger, SpeedLogger, WaterLogger etc. including an OilLogger, even on the V8 at version #941[1]0035

3. Current diagnostic software solutions

...

4. Communication

...

5. simple python program to query ECU

The current state of each ECU parameter (Throttle position, Lambda sensors, etc..) is stored in the ECU at a specific memory location.
The ECU Diagnostic Software simply queries and displays these memory locations.
Communication with the ECU is a simple serial connection. All you need to do is open a socket with the correct baud rate and you can freely query any memory location you like.

There are some extra files bundled with the Original ECU diagnostic software.

If you look in one that ends in .ECF you will see something like this:

[RealTimeStart]
#Title,legend,units,max,min,command,SamplingInterval
Throttle1,Throttle1,%   ,100.0  ,    9.48,9C
Throttle2,Throttle2,%   ,100.0  ,    9.48,94

What that says is: Throttle 1 is a percentage value ranging from 9.48% to 100% and it is stored in memory location 9C.