BMW AT200 Read & Write MSD81 ISN No Need Disassembling

This article mainly talks about the guide to read and write MSD81 ISN by BMW AT200 without opening the DME shell.


AT200 has updated to the newest version 1.6.1 on Nov. 19th, 2019.

Update info:
1. Added MSV80 read ISN, write ISN, Backup Data and Restore Data
2. Added MSD80/D81/D85/D87/MSV90 write ISN
3. Added the engine type of the TC1766:
Alfa Romeo, Audi, BMW, Citroen, Dacia, Dodge, Ford, Hyundai, Indian, Kia, Lada, Lancia, Nissan, Mini, Opel, Peugeot, Polaris, Renault,
Saab, Sea Doo, Seat, Skoda, Subaru, Suzuki, Toyota, UAZ, Vauxhall, Volkswagen (VW)


How to use BMW AT200 to read & write MSD81 ISN

All need:

DME module: BMW MSD81

Device: BMW AT200 ECU programmer+ professional read ISN OBD cable

bmw-at200-read-write-msd81-isn-1 bmw-at200-read-write-msd81-isn-2



Open AT200 software

Select car brand, model and Engine- EGS


Enter main menu

Here can see 7 options incl.

Wiring diagram


Modify VIN

Read ISN

Write ISN

Backup data

Restore data


Click “Wiring diagram” to connect MSD81 DME and AT-200 via OBD cable

bmw-at200-read-write-msd81-isn-4 bmw-at200-read-write-msd81-isn-5

Select “Identification” to read DME model info

Click “Read ISN”

Verify ECU authorization successfully

Read out ISN


Select “Write ISN”

Backup the data read out


Fill in the new ISN


Write ISN successfully


Read ISN again, confirm the ISN read out is correct


Finally, click “Backup data”

Backup data successfully


BMW AT200 V1.6.1 ECU programmer & ISN OBD reader:

Professional OBD Cable to read ISN:


That’s all!

Author: admin