Wellon/Xprog read 5P08 EEPROM for MB C204 ECU adaptation

ECU Chip Tunning

Purpose: accommodate the ECU ME2.8 of second hand, to back up the flash and epprom and to adapt the ECU of second hand to Mercedes C240

I have: a ECU ME28, a broken Mercedes C240 gives me failure in SD Connect C4

I got an ECU with the same numbers A 030 545 58 32 and 0 261 206 968, both HW 01.99, both Q01 BENZIN, the original FD 00M07 and FD 00M06 the second.

I have the SD4 Connect with development version, with DAS / XENTRY

I have a programmer a TL866A minipro, to read out the EPROM

Here you go…

Pretty much any ME 2.8 hardware will do as a replacement however they might come from a different displacement (remember these were coming in 2.6 and 3.2 variants) and other details might not match.

If the difference is only the FD number it does not matter, it will function okay.

If the original ECU has still functioning FLASH and EPROM you might want to transplant these two to the new box and you are good to go.

Otherwise you need to reprogram 5P08 to virgin, if you need details on this let me know (preferably on public so everyone can benefit) and i will give you quick tour on how to reset this ECU

Now, I’m going to have to put a virgin on 5P08, and i’ll explain it better than better, because I’m crazy about this, and I also prefer this to be public, so that more people can see and learn.

OK so what you need to do is to read the 5P08 EPROM load it up into an editor and
go to this offset: 0x98 (hex)

the value should read 40 hex

change to 08 hex, save, write eeprom and resolder. The ECU should be ready for initial startup now.

If that didn’t work try writing 08 hex in the same offset.

…and since you have the virgin ecu to be installed now, you might want to perform the Initial Startup with take over settings from the old ECU.

Note: The solution will work for the whole ME 2.8/2.8.X series ECUs, no matter of number of cyllinders, displacement, kompressor/or not.

Q: No need to change the VIN in 5P08 in the same time ?

A: Well you can, but once the unit gets reset to NON PERSONALIZED state the VIN can be easily overwritten by DAS during the initial startup process. My personal advice was always to change the EPROMs as less as possible and carry on further changes via the officially available tooling.

Q: even in a Smart, the VIN matters but now I know that in the ME2.8, the vin maching isn’t needed.

A: As for the stored VIN, this is again, an aesthetical issue here. Neither the ME2.8 or EZS nor any other component in the car will care if the VIN in the ME matches the EZS or not. It is just an identification, that’s it.

This is actually true also for CR3, CR4, ME2.0, 5/6 cyl MSM turbodiesels, CR2 and many other older ECUs.

Q: I bought a miniipro tl866a and it does not write the 5P08 EPROM.

Can someone advise me a programmer for the 5P08 EPROM, which is not very expensive.

A: Actually for all sort of chips i am still using a venerable Wellon programmer, VP-280 (i believe it was obsoleted by newer models). I did like, few thousand chips with it and apart from bricked firmware (that i did myself by accident) of the programmer, it was a rock solid tool in the workshop.

Occasionally i am also using Xprog-M which does fine job when it comes to programming EPROMs, Motorola MCUs and such.