No lights or dash light

1987 LR90.
Couple of weeks ago the lights wouldn't work, messed with connector from light switch and came on. Next Time I went to start, again no lights, but not the connector.
Checked continuity through switch and there was none for side or dip. Bought a new switch, tested continuity and all ok between brown live feed and side/dip. Connected up but still no lights?
Checked brown wire and showing as 17v??
Checked red wire to earth and there is a short! (I also checked the wires with the connector apart for the switch)
I know the red wire goes to dash lights and side lights, disconnected the dash binnacle but still shows as an earth on the red wire.
Any idea where the 17v would be coming from? (there's only 12v at the battery, engine not running)
God knows how I'm going to find the earth fault, the wiring diagram shows the red going to the fuses? then off to the lights etc. There has also been other things tapped in like a lights on alarm (that doesn't work)
So, any suggestions are welcome.

do you have a small fuse box under the bonnet? if yes, check one of the big blue ones!

or, pink relay behind dash binnacle

also, is it sides, dip/main and rear lights not working?

Thanks Mojo, I think there is a fuse box with large fuses under the bonnet somewhere and yes, there is a pink relay behind the binnacle, what is this used for and is it a normal type relay just pink in colour?
As you can tell, I'm fairly new to messing with these but worked for BT so understand basics of electrickery

edit
Yes, no lights at all, side, dip, or rear....not sure about main but I did hear the relay operate when I hit the flash stalk

the pink relay is the dim/dip relay

I've had similar probs over the past few months.

1. all side and rear lights worked but no main light. full beam worked from (horn/indicator) switch when pulled and pushed forward. This was found to be the pink relay
2. main and full beam worked but no side or rear lights or dash indicator. this was the main light switch.

mojo247 said:

the pink relay is the dim/dip relay

I've had similar probs over the past few months.

1. all side and rear lights worked but no main light. full beam worked from (horn/indicator) switch when pulled and pushed forward. This was found to be the pink relay
2. main and full beam worked but no side or rear lights or dash indicator. this was the main light switch.

Click to expand...

I have no lights at all, but will try the dim/dip relay. Ive found a supplementary diagram in the Haynes manual for the Dim/Dip circuit.....another avenue to go down

mojo247 said:

do you have a small fuse box under the bonnet? if yes, check one of the big blue ones!

or, pink relay behind dash binnacle

Click to expand...

Well I never, it looks like it was something to do with that large fuse under the bonnet, it was 30A and had blown sometime in the past and the previous owner wrapped Fues wire around the spades, I guess he didn't have a spare one and this was going g to be a 'Temp' fix, that has lasted 5 years, not bad I guess. I made sure there was a decent contact and it works again now! Think I'll have to invest in a couple of fuses for it.
Not sure why the voltage measured 17v and wouldn't switch through the light switch though (it does now). and I'm guessing the earth I was measuring at the switch was through the bulb and to earth, not a full earth but a resistive one.
There was me thinking its a basic vehicle with basic wiring, well, compared to modern ones I guess it is
Thanks again Mojo for the assistance

glad it's fixed! it's all you don't need at this time of year!

before anyone starts to fiddle with the wiring, it's definitely worth checking the fuses, bulbs, light switch, pink relay and as a last resort, the indicator/horn/dip stalk.

then you can get onto earths and the like!