Ok , Generally all that is read in the 996TT or 7.8 DME is 64K . This is also the same for the 7.2 DME in which was used from the 1999 C4 and Boxster MY2000 to 2001 996 or 2002 Boxster. The same further applies to the 997 7.8 40MHZ unit. The reason being is that the area that is read has the data required for the retrieval of the original Porsche files. We could read out the whole DME yet it would take more time and it is not required. Why read a full map given it would be the same as what would get compiled from Porsche.

 

I guess I should ask who would like to see an actual map from a car? It is not much to look at yet you could see what a tuner sees before it is broken down. I would have to upload a 7.2 file that is 512kb. The others such as 7.8 would be 1MB and the DFI cars are 2MB. When you look at a 512k size you can imagine how the others are.

 

I would like to see some screenshots from your tuning software

Thank you Scott

 

I would imagine it's just a list of hex code that if you don't know the locations of various tables it would be useless.

 

Yes it is however I was not sure if everyone knows what Hex is You do get points though for knowing . I could show the basics ..... Then again it would be Hex highlighted.

 

I have attached a 2001 Boxster file for any who may want to look at what a Porsche file is or even just HEX. This can be saved , unzipped and then opened with either a HEX Editor or Notepad. An Editor is what I use many times for work on them. This is just something to look at.

 

I don't believe Notebook will show you hex so you'll probably need a hex editor.

 

Hi Scott,
I am a long time programmer (non-automative) I have some general Q's about the Porsche's that are more on the technical side. I have done some hobby programming with my previous cars in the past. In doing so I realized how little public information there is out there about the subject.

I was wondering how cooperative automotive/parts manufacturers are when it comes to accessing their modules (i.e. protocol/commands/authentication). From my experiences I have learned that it's one thing to send commands to a control cluster to read out settings, but it's another thing entirely to perform the "authentication hanshake" procedures required to change settings in a module. I always wanted to know wether they provide you with some official documents or just kind of just leave you to 'figure it out' on your own. I obviously don't want you to share any proprietary info, it's just something I have always wanted to ask someone who has a lot of experience in automotive programming.


Thanks-
John

 

Does the DME have control over functions like stability control (PSM), traction control (PTM) and the new rear diff control (Torque vectoring)? Or is this controlled by a seperate ECU?

I find the system much too intrusive on the 997.1 for track driving but see how it could be advantageous if programmed for performance and not just safety. I believe there have been updates and the new torque vectoring feature on the 997.2. For track driving, I can see a lot of benefits if this could be tweaked (turn off stability control while having traction still active as can be done in the GT2), or even driver controlled for different types of tracks.

Thanks.

 

As a rule at least with the European cars they do not offer any. Typically there are not many Porsche tuners and fewer that can actually flash a car in house. The flashing drops even more with the newer DFI cars . This is not to say that they cant be flashed on the bench yet via the port is a different story. When accessing the dme via the port there is a strict protocol for the access and the level of access. Some of the things that have to be figured out to access them is the "authentication handshake" in which seed keys are required and in some an RSA code. This is the point many get stuck at. Many use third party flashing software or hardware for this reason.

The next hurdles would be the actual programming and Porsche is different than the others. The DME's may be similar to other brands yet the code is not and has to be learned. There are such programs as WINOLS that checksum modules and basic id's can be used however it does not tell you what the map is or what it does. The tuner has to figure it out. When tuning Porsche though you come to understand what the Identifiers are for these. There are other programs that will identify specific maps yet the are not enough as one would rather delete the boost control for a Greddy than raise the identified boost tables as an example.

The highest level or most beneficial would be the use of the Bosch software that created the files and maps to change and alter them. These files are called DAMOS files and to have these for each car and the software works the best. The main problem is getting them. Porsche does not allow these out yet some have made it.

These ar just some points that hopefully answer your questions.

 

Scott , i would like to ask you something please ,
when useing methanol 100% + 93 pump gas in 28c weather !! what timing degree should i see in the data logs ??

 

The control of the PSM/ABS is in the control unit itself. This control unit is the black box that is attached to the pump and what the electrical wiring attach's to. These units as a whole are write once in which they cant be programmed again. The 1996 993 DME was also like these as they were write once only. These DME's though can be reconfigured for different chips so they can be reprogrammed. The PSM/ABS unit is a different story.

The different cars have different PSM/ABS units such as the GT2 to the 997 Turbo. These units are preprogrammed to different values. The 987 to 997 is also different etc. The values are also so configured that they keep the car line in its place. A Cayman units values are set so that it handles well yet since it was not made for racing does not do well with slicks on the track unless altered.

I have for many years reconfigured cars such as the Cayman's in which I may have installed a 3.8S or X51 engine and then changed the CAN configuration and PSM/ABS so it actually ran as a Mid engine 911 in which does not exist. These cars have no issues with the PSM being intrusive. I also get many to fix after such said conversions.

Some of the changes could be to the DME as the PSM/ABS unit relies on torque values from it. The DME is an input. This will not change what the PSM/ABS was programmed to yet how it acts on what it receives via CAN.

 

You should send me the logs and I will look at them. Lets do this via email.

Thanks,
Scott

 

so scott a question to one of your response, how do you or any body else figure out the auth code and the rsa pass key ( i am assuming) , almost seems like you have to hack it? because even if you use third party software and wipe every thing out, then how does porsche read the dme once that is done because all the porsche specific auth code and rsa would be wiped out then ?, am i missing some thing here

Ronnie

 

Very interesting!