Question:
Added JLR news keys on bench into other slots but they do not have sync code.
Solution:
How the Sync Code is Maintained via the Dump?
When you use a programmer (like VVDI Prog) connected to the MCU via an adapter or solder points:
The Sync Data Already Exists in the Dump:
The hidden cryptographic sync block (which pairs the KVM/RFA to the Body Control Module and Engine ECU) is already written inside your original MCU data dump.
The “Immo Data Tool” Preserves It:
When you load your original D-FLASH and EEPROM data into the Xhorse Immo Data Tool, the software reads the entire file. It identifies the empty key slots while strictly leaving the vehicle’s pre-existing module sync codes completely untouched.
The Key is Synced to the Dump:
When you place your blank Xhorse JLR key onto your tablet and click “Generate Key”, the tool reads the exact rolling-code seed and sync blocks from your dump file and injects them directly into the transponder chip. It then outputs a freshly modified file containing the new key data.
Writing Restores Sync:
When you write that newly generated file back to the MCU, the module retains its exact original synchronization with the rest of the car, but now recognizes the new key as a valid, synchronized device.