NefMoto

Technical => Flashing and Chipping => Topic started by: EbikeSam on April 29, 2026, 06:33:59 PM



Title: Bosch M5.2 OTP for M73/Looking for options
Post by: EbikeSam on April 29, 2026, 06:33:59 PM
Hello everyone,

I am seeking as much information on a Bosch M5.2 running a M73B54 V12 engine. The challenge I am faced with is the discussion that these DME are equipped with OTP (one-Time Program) chip. I own a 97 BMW E31 850ci equipped with:

ECU Make: BOSCH
ECU Number:M5.2
N ECU:621-0.408
Eprom:29F200 PSOP
CKS:AF8F

 I am looking for possible options to get around the OTP chip. I have also "heard" that it may be possible to rewrite or get around the OTP aspect with a Galletto 1260 via OBD (The eprom is flash type 29F200 PSOP which can be flashed with right gear?) Anyone with any experience with this DME equipped with a supposed OTP chip hopefully you will chime in and give me some insight or direction with possible options. I really do not want to go with a Standalone, I would rather find a way with the original DME/ECU so retain as much of original equipment as possible. I have been researching & looking for months so I am committed to finding an answer.

I greatly appreciate any support I can gain! Thanks in advance