Controller Area Network (CAN)
WARNING: This page is about a different car, the 2003 Jaguar XJ8, 2003 Jaguar XJ, 2002 Jaguar XJ8, 2002 Jaguar XJ, and 2001 Jaguar XJ8. However, it is still accessible from the selected car via links, so may be relevant.
The TCM is an integral part of the CAN system which facilitates the interchange of real-time data between control modules and sensors.