Secure Diagnostics, introduced in August 2025 with the 26MY Defender and Discovery vehicles, enhances the protection of onboard diagnostic systems. It does this by restricting diagnostic communication with the vehicle’s networks until the system is unlocked by an authorised tester.
The unlocking process is fully integrated into all TOPIx applications. Users can easily check the vehicle’s lock status via a padlock icon displayed in the top banner of the TOPIx interface, next to the ‘Ready’ status.
Padlock Icon Indicators:
. Green Padlock:
The vehicle is either not equipped with Secure Diagnostics or the module is already unlocked.
. Red Padlock:
The vehicle is Secure Diagnostics enabled and the module is currently locked. It will automatically unlock when a supported diagnostic application is launched.