DTC U1A14-49: CAN Initialization Failure - Internal electronic failure: Action

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 2015 Jaguar XKR-S, 2015 Jaguar XKR, 2015 Jaguar XK, 2014 Jaguar XKR-S, and 2014 Jaguar XKR. However, it is still accessible from the selected car via links, so may be relevant.

Clear the diagnostic trouble code and retest. If the problem persists, configure the module using the manufacturers approved diagnostic system. Clear the diagnostic trouble code and retest
If the problem persists, renew the rear differential control module. Refer to the warranty policy and procedures manual, or determine if any prior approval program is in operation, prior to the installation of a new module/component