Baud Rate Sync Issues: Troubleshooting Guide

Hello friends.
Can someone help me? I'm having problems with the immobilizer system in my Audi A4, year 1996.
'The Steuergeret (control unit) is not responding, and I keep getting errors related to baud rate synchronization.'
I can already access and read data from the engine control unit and the air conditioning system.
Thank you.

Hello Nemin,

What kind of diagnostic adapter do you have? Is it one of the ones offered here in the shop?