DTC U0402-08: Invalid Data Received from TCM - Bus signal/message failures: Action

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2015 Jaguar XKR-S, 2015 Jaguar XKR, 2014 Jaguar XKR-S, 2014 Jaguar XKR, and 2013 Jaguar XKR-S. However, it is still accessible from the selected car via links, so may be relevant.

Using the Jaguar Land Rover approved diagnostic equipment, check transmission control module, for DTCs and refer to the relevant DTC index
Using the Jaguar Land Rover approved diagnostic equipment, complete a CAN network integrity test
Refer to the appropriate electrical circuit wiring diagrams and check high speed CAN bus circuit for short circuit, open circuit