Which tool can read BMW X1 CAS3 OM23S eeprom

I have a client that requires a spare key on this BMW X1 2014 CAS3+ with OM23S mask.
I have Xhorse BMW Multi tool but it says that the CAS is ISTA-p4* so need to downgrade flash. It says that if you have a working key then do not downgrade but rather read eeprom by BDM and then use the option which says make key by eeprom.


Why I can’t do it by obd? I have the latest version 7.7 and firmware updated. Can connect but not read eeprom, it throws “disable security error”. Doesn’t ask for a flash update too.

Problem now is that the MCU is 0M23S mask. I tried with R270 as 0L15Y and also 1L15Y but it says the chip ID isn’t correct. It give another ID. So any ideas how to make the spare key? Which programmer will read this MCU, xprog clone?


Suggestions by experienced locksmith:


You can read it with xprog clone same connection as 0L15Y. Xprog version above 5.0, Xprog 5.0 doesn’t show that Mask Set.


Xprog v5.5.1 work super ok on this mcu. see picture below:

xprog read cas mask 0m23s



here is the free xprog v5.5.1 atmega and eeprom help you update your x-prog m.


We have not hold the responsibility if you damage your device. Better to buy higher version Xprog v5.55 or V5.60.



I tested all CASs with all mask with VVDI Prog..buy it ..
It’s safer. It is getting updates, and can do many BMW ECU.


BMW Multi Tool can not add spare key for this model via OBD, can be done only via BDM. You need first read eeprom by using Xprog above version 5.0 or VVDI-Prog ecu programmer.