Bricked CAS/EEPROM/Flash

**jsnlam** · 1st August, 2024, 12:46 PM

I tried to DIY create a spare key for my BMW E88 with xTool D7S via OBD and it required downgrading of CAS. The process failed and now the car does not respond to the key.

I did some research and it seems the problem is either in flash or EEPROM, and they need to be re-written.

Now I have taken out the CAS (model 9287535-01), tried to connect it with xTool D8S and KC501 but I couldn't get access to the function relevant to Flash/EEPROM. It seems I got the wrong tools.

I would be grateful if someone could advise what I can do to revive my car. Should I get some bench tools and learn how to fix it? Should I get another 2nd handed CAS and make it work on my car?

Million thanks for anyone who can help.

**maxonde34** · 1st August, 2024, 02:00 PM

You need a programmer like VVDI Prog and to solder cables to the PCB to get direct access to the MCU

**jsnlam** · 1st August, 2024, 02:15 PM

Originally Posted by maxonde34

You need a programmer like VVDI Prog and to solder cables to the PCB to get direct access to the MCU

Thanks a lot! I just figured out that probably the D8S I got has some problem so it cannot work with KC501, which is something like VVDI Prog. I have already ordered another tool to see if I can make use of my KC501 before getting another tool.

I have also taken the CAS out and tried soldering the cables to the PCB. Hope the new tool can read the files on it so at least I can check the status of the CAS.

I notice that some people use tools like Kess and Ktag. Are they useful and worth getting for fixing cars in the long run?

**jsnlam** · 1st August, 2024, 05:55 PM

I have just been able to extract the EEPROM and FLASH as attached. Could someone help fix it? Thank you!

**jsnlam** · 1st August, 2024, 11:33 PM

I have found one thing called CAS 3+ editor and found that the EEPROM is normal except it's in boot mode. I still haven't figured out how to change the hex codes to make it normal again. Does anyone know how to fix it? Thank you.

**askkey** · 2nd August, 2024, 11:43 AM

I have done the basic modification to get it out of BM. But you most likely have other issues with your files.
I haven't checked your flash so that might be bad as well.
If you have communication and some limited functionality after this try to reflash it over OBD with a good file.
And you may need to sync the ELV. DME and CAS.

Either way, test and report

**Silva1337** · 2nd August, 2024, 12:41 PM

there is fixed files and working solution

**jsnlam** · 2nd August, 2024, 02:29 PM

Originally Posted by Silva1337

there is fixed files and working solution

Oh your file is password protected. May I have the password?

**jsnlam** · 2nd August, 2024, 05:50 PM

Originally Posted by askkey

I have done the basic modification to get it out of BM. But you most likely have other issues with your files.
I haven't checked your flash so that might be bad as well.
If you have communication and some limited functionality after this try to reflash it over OBD with a good file.
And you may need to sync the ELV. DME and CAS.

Either way, test and report

Thanks a lot! I just opened it with CAS3+ editor and it says it's still in boot mode. I will try to write it to eeprom and see it works on the car and let you know

**jsnlam** · 5th August, 2024, 09:11 PM

Originally Posted by askkey

I have done the basic modification to get it out of BM. But you most likely have other issues with your files.
I haven't checked your flash so that might be bad as well.
If you have communication and some limited functionality after this try to reflash it over OBD with a good file.
And you may need to sync the ELV. DME and CAS.

Either way, test and report

Hello. I just wrote the revised EEPROM and tested. The car still doesn't respond. So perhaps it's still in boot mode... Thank you for your help though. Do you think there is anything else that can make the file work?

Separately, may I know is there any free/cheap software I can edit the EEPROM containing the encrypted hex codes? If I can do that, I can use a normal file and change the VIN & other codes to make it work for my car.

**rob h** · 5th August, 2024, 09:53 PM

Try another full cas file. Then check is you can connect by obd. Wake up cas, by pressing start button. Or created a key.
Get a non + version,.

(full eep and flash. no need correct sw. Just take same mask, same size.)

You might have fried something, whilst reading with the programmer.

And do check, with magnifier, or zoom phone cam. If you bridges something with solder residue.

If all is well, then again try the given solution.

**richard27** · 6th August, 2024, 01:17 PM

hello I am trying to learn these are the files you are looking for your flash file is corrupted the screen does not come in eprom boot mode write 111 file to eprom write flash check

**jsnlam** · 6th August, 2024, 01:41 PM

Originally Posted by richard27

hello I am trying to learn these are the files you are looking for your flash file is corrupted the screen does not come in eprom boot mode write 111 file to eprom write flash check

Thanks a lot! I just realised that I need a flash file too! After I have written the EEPROM and flash, I found that the battery is not flat. Need to get it charged before I can test it out.

**jsnlam** · 6th August, 2024, 01:44 PM

Originally Posted by rob h

Try another full cas file. Then check is you can connect by obd. Wake up cas, by pressing start button. Or created a key.
Get a non + version,.

(full eep and flash. no need correct sw. Just take same mask, same size.)

You might have fried something, whilst reading with the programmer.

And do check, with magnifier, or zoom phone cam. If you bridges something with solder residue.

If all is well, then again try the given solution.

Thank you for the tips. The car battery is completely flat now. I will get the battery charged and try.

Wish I had seen your post earlier as I accidentally put some solder in between a chip's legs and it took me a long time to clean it up before I could write the EEPROM and Flash files.

**jsnlam** · 6th August, 2024, 06:19 PM

Originally Posted by rob h

Try another full cas file. Then check is you can connect by obd. Wake up cas, by pressing start button. Or created a key.
Get a non + version,.

(full eep and flash. no need correct sw. Just take same mask, same size.)

You might have fried something, whilst reading with the programmer.

And do check, with magnifier, or zoom phone cam. If you bridges something with solder residue.

If all is well, then again try the given solution.

I just hooked my car with another car by jump start cable through the terminals in the engine compartment. Try to charge a bit but no light on on dashboard - not sure if this is normal if battery voltage is too low (it's about 7v now). I will try to use a spare car battery to recharge it and hopefully the dashboard would come on... It's difficult to get it charged without car battery charger, and I don't want to keep a car on for too long