BDM vs OBD - different readings

by **Alex.T** » Sun Jun 14, 2015 3:03 pm

So I'm new to BDM and I have a Peugeot 407 2.0 HDi with Siemens SID803A ECU.
Using Galletto v54 i read the flash via OBD and BDM but they are different :shock:
Can anyone explain to me why is that?

Also, when I put it in WinOLS, with BDM file it finds potential maps, but with OBD file it doesn't find any map.
Isn't that strange?

I plan on tuning the file and then write it via OBD with Galletto.. Which one should I use?

by **Alex.T** » Fri Jun 26, 2015 4:35 pm

no one?

by **tehnosoftex** » Fri Jun 26, 2015 5:43 pm

Hi, when you read by bdm, your tool will read all the ecu files, including processor internal flash and external flash. Wen you read by obd, your tool will read only a piece of the external flash but will keep the file size replacing the unreaded part with FF.

by **Alex.T** » Fri Jun 26, 2015 6:11 pm

Thanks for the info.
So which reading shoud I use for writing via OBD?

by **tehnosoftex** » Fri Jun 26, 2015 6:16 pm

Obviously you must use the obd reading for write on obd. If you use the obd reading for write on bdm you will ruin your ecu, because you will write only a part of its program. The obd reading, writing is used for tuning, dpf off, egr off etc. It has all maps included, but if you want to clone an ecu with another from scrap yard you will have to use bdm reading writing. It is no harm to write the bdm reading on obd since the obd tool will use only a part of that file but there are tools, like Galletto54 which will refuse to write a bdm file over obd.

by **Alex.T** » Fri Jun 26, 2015 7:01 pm

Very good info!
Appreciate it, thanks :thumbup:

by **EDC16U1** » Thu Apr 28, 2022 12:54 am

tehnosoftex wrote:It is no harm to write the bdm reading on obd since the obd tool will use only a part of that file but there are tools, like Galletto54 which will refuse to write a bdm file over obd.

It is old thread but i think it is still alive and relevant.
which tools they are then? as you say Galetto54 refuses to write a bdm file on obd? Can MPPS write a full bdm backup file on obd to EDC16U1? thanks

by **Shooting** » Thu Apr 28, 2022 7:46 am

EDC16U1 wrote:
tehnosoftex wrote:It is no harm to write the bdm reading on obd since the obd tool will use only a part of that file but there are tools, like Galletto54 which will refuse to write a bdm file over obd.
It is old thread but i think it is still alive and relevant.
which tools they are then? as you say Galetto54 refuses to write a bdm file on obd? Can MPPS write a full bdm backup file on obd to EDC16U1? thanks

MPPS is an old tool, I flash BDM via OBD with Kess no problem.

wbr

by **EDC16U1** » Thu Apr 28, 2022 9:34 am

Shooting wrote:MPPS is an old tool, I flash BDM via OBD with Kess no problem.

wbr

I have got only an MPPS V16 (EU) and will be the only tool to read, write and if needed recovery.
So the question, for me to find out, still remains: Can MPPS V16 can write full BDM backup file on OBD, or as EDC16U1's OBD and BDM reads are full and identical, without needing a BDM, perhaps only writing a stock OBD read via OBD will be enough to recover the ECU?
Thank you. Kind regards

by **Shooting** » Thu Apr 28, 2022 10:05 am

EDC16U1 wrote:
Shooting wrote:MPPS is an old tool, I flash BDM via OBD with Kess no problem.

wbr

I have got only an MPPS V16 (EU) and will be the only tool to read, write and if needed recovery.
So the question, for me to find out, still remains: Can MPPS V16 can write full BDM backup file on OBD, or as EDC16U1's OBD and BDM reads are full and identical, without needing a BDM, perhaps only writing a stock OBD read via OBD will be enough to recover the ECU?
Thank you. Kind regards

MPPS V16 has NO BDM translators, if the file isn't a true OBD Check summed file then it will probably brick it.
Then recovery MUST be then done with an OBD file with correct Checksum.
Some EDC16 ECU's will require a BDM restore, which is why you need proper tools to do the job.
If you love your car then don't risk a cheap china clone tool on it.

wbr