DTC U0400-81: Invalid Data Received - Invalid serial data received: Action

NOTE: This is not a vehicle harness issue or anti-lock brake system control module issue. The data source module has sent information which it has marked as Invalid

Using the Jaguar Land Rover approved diagnostic equipment, check the snapshot data to determine the missing message source control module. Check the relevant control module for related Diagnostic Trouble Code(s) and refer to the relevant DTC index
Alternatively, follow the guidance below
Using the Jaguar Land Rover approved diagnostic equipment, check the ECUs below for any relevant network Diagnostic Trouble Code(s) set and perform the relevant corrective actions
Body control module, chassis control module, all wheel drive module, restraints control module, driver assistance domain controller, brake system control module, instrument panel cluster control module, near field sensing module, powertrain control module, transfer case control module, gateway module, steering angle sensor module, power steering control module, battery charger control module, HVAC control module, infotainment gateway module, gear shift module, transmission control module, terrain response
Using the Jaguar Land Rover approved diagnostic equipment, run the on demand self test and check for internal faults set on the ECU mentioned on the previous step
Perform an ignition cycle, clear the DTC and retest, if the problem persists contact JLR technical assistance