no dash light

my major weakness is electrics wires fuses relays switches so no surprise I have been easily stumped by no lights on speedo temp gauge fuel gauge think every warning light works ok as do all exterior lights fans etc so could it just be a fuse? which one? its on my 1990 110 defender truck cab thanks

The Haynes diagram, which isn't always the best source, says that the power for the instrument lights should come from a red wire from the light switch, and that it doesn't have a fuse. The same wire passes the fuse box and supplies power to the two fuses for the left and right sidelights and number plate light.

I've not had a 90/110 that new, but they used to have a switch that let you switch inst lights off. Haynes shows that being deleted from 1986, but I don't know if that's right.

Unless someone else responds, I'd first check that the sidelights work. Then that there definitely isn't a switch that you've not noticed. If not, you need to check the red wire that comes from the instrument lights to the fuse box looking for disconnection or damage. If it is this wire, my bet would be damage/disconnection behind the instrument panel because it's really too small a space for everything that's rammed in there, and connections get shoved and vibrated until they fail.

many thanks boguing that gives me something to work on will keep you updated

Just a thought - check your dash lights off/interior light switch.