I've started putting this '94 K1100LT back together after a respray. Got the main fairing back on and put the tank on this arvo. The low fuel light don't work, I'm sure it did before I started. With a meter on the tank cable, I see the variable fuel indication working but not the low fuel switch indicator. Bugger. Do I need to disconnect anything internally before I pull that assembly out of the tank? Haven't had to pull one out before.

I can hear the pump going so it should start with fuel in the tank at least.

Also got no rear brake lights and the triangle on the dash doesn't light up either, that'll be next.

Check the multi-pin connector on the back of the instruments cluster. Sometimes, just unplugging and replugging resolves these types of failures. Inspect the pins and sockets to ensure they are clean. If you give the pins a slight twist with a pair of needle nose pliers, they tend to make better contact.

Good luck with your troubleshooting.

Regards

No, I'm measuring at the tank and it's always open circuit. 
I need to pull the sender from the tank.

Never mind, I see it.
RTFM and I found a F'ing manual to read

Fixed it but the issue is a bit of a worry. A bit of the printed circuit on the low fuel indicator board looks to have blown like a fuse. It sort of reminds me of a detonator   

I soldered a bit of wire in there and it's a worker again. I added 6 liters of fuel and the low fuel lamp went out.

 

Worrisome Robin.  Can you think of any circumstance during reassembly when the low fuel indicator pin might have come into contact with 12V directly?  If 12V was applied directly to that lead, there would be a short to ground through the contact pad and the wiper arm.  It looks like the PC trace melted, being the weakest link.

zactly rob ....just what I was thinking ...seen a bit of that type of fault ...trying to think how that might have occurred ...there aren't many connections I can think of that are similar ...except maybe the gear indicator connector ?

I didn't zap it, the bike got stripped for paint as soon as it arrived here. 

It does have a non standard plug on it so maybe whoever put that on did it ?

I thought I checked it was working when I drained the fuel but I've been changing bikes like sox over the last few months so that may have been another one  

You mentioned in your first post that it worked before the respray, so the PO couldn't have done it.  Point is, it's good that the problem is fixed now.  BTW, you've got an immaculate fuel sender; it looks nearly brand new.

Yeah, I thought I'd checked it when I emptied the fuel. I'll need to get myself a checklist going for next time.

Brake lights came good today as well ?  dunno why fixing the tank would effect them but they now work and the Bike started on second push of the starter. Whoohoo getting close now.

hmm   I suggest changing the tank plug for something  ....erm a little more polarised by design ??? perhaps ?

Maybe he got white and green crossed. 
That would do it, once you switched the key.
But I'd have thought that would also blow the tank up  ?

lol.... well that is kinda unbeatable ,...

yeah he must have

no mate it would just sit there and sizzle .....a spark or in this case heat ... in the fuel does nothing till it hits oxygen in the right proportions

But there is no circuit until there is no fuel. I'm guessing the sensor is still submerged when low fuel is active.

Who's a lucky bastard...