[B1257]

Accually I dont know, because of old chassis use 1 time programmed EPROM, which is UV eraseble.. So no any chanses to reprogram it via diag socket... All the thing starts from E36(restyling) and E39... etc at those years

This is not correct, old ECUs like BOSCH M1.1 (325 E30, E28 and more), M1.3 and M1.7 had a special reseverd data area inside the Eprom. This area was used for variant coding and small updates. Programming was made wih DIS and MODIC. The System was working with jump adresses inside the Eprom.

Take a look here:
Programming an engine control module is necessary when:
• Installing a replacement basic control module
• Recall or Service Action campaign: This falls into one of the following catagories:
- Program update to existing program
- Complete programming procedure after EPROM replacement.

Programming a replacement basic control module
Control modules are received from the parts department in the basic state (EPROM loaded only with resident data). These control modules require programming using the DIS/MoDiC and the latest programming software.

Programming Update Updates are refered to as "Customer Service Measures" in the programming software. The existing program in the control module is amended with an updated program. This new data changes various operations of the existing control programming. Program updates write the new data in a reserved section of the EPROM. The location of the old data is overwritten with instructions for the DME to search the reserved section in the EPROM when the function is required.

Because of limited space on the EPROM, program updating can only be done one time.

The DIS/MoDiC will display the message "Measure not applicable to the control module version" if update has already been done or the DME is factory updated.

Best Regards,
B1257