I implemented this the other day and it works.
I want to know HOW it works though, but that doesn't seem to be an option.
I read through the datasheet but nothing really stuck out.
Very late to the game, I know, but I just figured it out this week (how the ROM patches work in the MKIV VDO clusters, not (yet) how the needle sweep patch works). The EEPROM not only contains settings but also a small patch block. The Micronas chip has a ROM patch module that allows for up to 10 ROM locations to be overwritten with patch data. When the cluster powers up, it loads the patch block into RAM, checks it to make sure it's valid for the cluster ROM version, then sets up the ROM patch module using data in the patch block. This causes a few places in the ROM code to jump into RAM where the patch block was loaded. I'll write up more details soon.
I wrote some open-source software that I use to read/write the EEPROMs in MKIV clusters (VDO, Bosch, Marelli), dump the VDO ROM, read/write the CCM EEPROM (like the ancient VDS-Pro), dump the EDC15 EEPROM and a few other things. Just needs a dumb KKL cable or VCDS with the VCP drivers.
https://github.com/gmenounos/kw1281test