MSX 150 / MSX 110 DIY ECU Reflash?

[HiPeRcO]

This Bosch ecu me7.4.4 is used also in cars like Peugeot or Citroen . The file size for the cars is 512kb . The file size for polaris is 240kb.

The main problem witch remains is the checksum. Without it the software for tuning the maps is unable to identify what model of vehicle is uploaded.

I would observe that the file size isn't correct, which would lead to checksum errors etc. Maybe for some reason you aren't getting a full readback of the flash, it should be a power of 2, like 256KB or 512KB. Can you read off the part number of the flash chip in the ecu?

[krammer226]

"I would observe that the file size isn't correct, which would lead to checksum errors etc. Maybe for some reason you aren't getting a full readback of the flash, it should be a power of 2, like 256KB or 512KB. Can you read off the part number of the flash chip in the ecu?[/QUOTE]"



I was thinking about this problem too. The hardware of the Polaris unit is different (compared to Peugeot ecu). The flash cip on both of them is 29f400
. When you hook up the ecu with ktag , the first thing is recognizing the ecu id . This is done by reading the maps( i guess).
For Polaris there is two protocols : 56 for bosch M7.4.4 and 57 for bosch Me7.4.4.
For Peugeot there is one protocol for Bosch Me7.4.4 which is 397.
Now , when i hit the read button on the ktag software, the program is trying to identify the ecu and the correct protocol. If i select a wrong protocol , the software tells me which protocol i select and which is the correct one to be selected.

So , with a wrong protocol , you cant read anything .

The Me7.4.4 has three files in them : one file is the main processor(st10c167) , one file is the flash(29f400) and one file is the eeprom (95160)

Because i have three ecu me7.4.4 (two for polaris and one for peugeot) , i try to compare the file size between them . The processor and the eeprom are identical size but different data (wich is normal )

I removed the flash chip from one Polaris unit and stick it in the Peugeot ecu , then i try to read it . The software automatically recognized the protocol 57 (Polaris) despite that i was connected to a Peugeot ecu. This result made me to think that the software is identifying the ecu based on the flash chip data.
Anyway , the result of reading was the same : 240 kb with a warning error at the end of the reading process( 'no checksum has been found')

My target now is to identify one standalone reader for this 29f400 and try to read it alone . If will get the same result then i do not know what can be the solution to be able to read the maps.

There is a possibility that polaris has splited the maps between the flash chip and the eeprom chip but this is just a theory .

[HiPeRcO]

29f400 is a 512kb flash. Reading it in a programmer will give you a 512kb for sure. (Then you can look for maps )

Seems like the ktag software isn't fully compatible with the polaris code. What other software can you try?

[Tony2k]

@krammer226: can you share please the ori file of your Msx? I want to show it at my ecu tuner, he remapped my ex Peugeot 206 with Bosch ME7.4.4.

[HiPeRcO]

@Tony2k: I would guess he might share the file when/if he can retrieve it successfully

@krammer226: Have you tried NefMoto S/W? http://www.nefariousmotorsports.com/...shing_Software

[ripcuda]

Welcome Krammer!
So nice to have a new person drop-in and share some good, new content!

This chip reading/reprogramming is not my forte... but I hear you mention checksum errors... and that reminds me of what Desperado said

I have also developed the required serial communication protocol and checksum recalculation to safely reflash these ECU's with custom tuned maps.

about checksum recalculation. But I don't know what that means.

I like where you guys are going with this!

Cheers!

[HiPeRcO]

A checksum in this context is used to verify memory contents. It is a number (or numbers) stored in the memory that will be different with only a tiny change in the rest of the memory. The ecu would use this to verify that the contents of the flash are valid, since corrupted numbers in a MAP might damage the engine (for example). So when you change MAP's (i.e. change the flash contents), the flash checksum needs to be updated. Bad checkums will cause the ECU to not even function. It may be that Bosch has some secret checksum algorithm, making this task more difficult (or worst case, impossible for us).

Full disclosure: I have never tuned an ECU before, nor looked at a MAP. I've only just started researching these areas. But I know a fair bit about electronics in general. And I did stay at a Holiday Inn Express recently

[krammer226]

Guys , i am trying to upload the files but i just cant . the forum accept onliy jpeg , gif , mov...

[krammer226]

Here you have the files from the polaris ecu

https://mega.nz/#!oocHxKbL!2rIVNZ-Nk...MdU055ixAjUmH4

[krammer226]

@Tony2k: I would guess he might share the file when/if he can retrieve it successfully

@krammer226: Have you tried NefMoto S/W? http://www.nefariousmotorsports.com/...shing_Software

Ok , this software is only for getting acces to the ecu thru the OBD port . we have a problem already since we don't have a obd port on polaris pwc. Second problem is that this software is only for reading the files and write them back on the ecu . no way to open or modify anything on the flash file .

Regarding the protocol that mr Desperado has developed , this is the protocol that i was saying that my ktag unit is recognizing automatically which protocol do i need for the connected ecu.

The name for the protocol that i am using to connect to ecu is P57 POLARIS MPE750 150 HP BOSCH ME7.4.4 (Among many others protocols used for different tipes of ecu i have also a P56 wich is used for polaris FS,FST BOSCH M7.4.4)

So , guess there is no way to be wrong except that the files for the pwc to be different than the files used on snowmobile.

I forgot to mention that ktag does not have a PWC section . The protocols that i found them for polaris me7.4.4 are under Bikes section .

So , the engine used on snowmobile and pwc is the same -MPE750-
The ecu used on both applications is BOSCH MPE750
The only thing that may be different is the flash content but i cant know it for sure unless i will have the chance to read one ecu from a snowmobile and since i live on a small island in the mediterranean sea (350 sunny days per year) there is no chance to find anyone riding a polaris snowmobile here .