Land Rover Repair: 99 Disco I, tail light/dash light problem

Question
I have a 1999 Discovery I that has tail/dash light issues, but only when it is cold.  In the winter months, when we start the car, the tail lights and dash light do not turn on until the car has warmed-up.  We have changed the fuses to no avail. Summer time- no issues whatsoever.  At what point are the tail lights tied to the temperature of the vehicle?  Any support will be greatly appreciated.

Answer
In that car the tail and dash lights are wired directly from the headlight switch.There is no complex computer control.  It's possible the switch is not making good contact because it's old.  Try wiggling.  Outside of the switch you just have the fuse box and wiring connectors, any of which can get flaky in an older vehicle.