Low range and diff lock lights flashing when starting 2018 VXR 5.7

[Andrew Dubai]

When ever i start the LC first thing in the morning the LO range and Diff lock lights are flashing. Only started since the weather cooled down. If i run the engine for a few mins and then switch off and on they dont come back on.

Garage has looked at it and says they cant see any fault. They are saying it maybe the battery is on the way out but checking the battery all the reports are good.