The Vehicle Management System (VMS) module resides inside the upper cavity of the Passenger Footwell.

It is the brains of the Roadster, contains a flash chip, and operates on firmware.

This part is not in production anymore.  Tesla may have dwindling supply left.  Spares are often harvested from donor Roadsters, the supply of which is also steadily declining.  

Fortunately, this part is repairable and rebuildable.  We have successfully reverse engineered this sub-assembly, and are offering full rebuild services, firmware updates, and flash chip replacement.