You can unlock/renew Audi S5 5th generation immobilizer key with a Xhorse VVDI mini key tool.
Unlocking work takes only 15 minutes.
Key type: Hitag VAG
Key marking 8T0959754S
1. Remove the key blade.
2. Remove the battery.
3. Remove the key board.
4. Solder the wires from the VVDI Mini key tool.
5. Press unlock.
6. Put the key back together.
7. Read the key again. It has been unlocked.
Select Remote Renew- Audi- IMMO 5th Generation Key
Check wiring diagram.
Solder wires to the key board.
Unlock remote.
Read key again. It has been unlocked.