Computer/Monitor inop on XJ ....HELP!

[Snake]

Problem.....computer/monitor wont come on.

Can anyone tell me what wire specifically does the computer/monitor on an 82' xj1100 get its power from? Looking at my schemtaic I beleive it is the White(W) wire going to the regulator/rectifier.
It is definately a power problem which I found out today, totally by mistake. I was changing the grounding strap on the battery because it was badly corroded and thought I would try and do some more troubleshooting on the computer/monitor which hasnt worked since I got the bike. Well I was thinking I might have a bad ground, so I diconnected the fuel sender connector under the seat which has a common ground with the computer and hooked a wire directly to ground on the battery(well i thought i had it on ground ..oops! keep reading) and the other end on the black wire of the fuel sender connection. Bzzzz....as sparks go flying! O.k that didnt work. Maybe the green wire is the ground. So I try it and presto the computer comes to life and I am overcome with joy. I had the wire hooked up to the positive side of the battery, so instead of giving it a ground I was sending it juice which is just what it needed. With my stupidity I partially figured out the problem...unreal! So now I need to find out why isnt the computer getting power like it is supposed to?? Could it possibly be the regulator/rectifier? I am suspect of that because the tachometer is also messed up(just bounces) and has something in common with it.

[Mike Hart]

Looking at my schematic I see a brown wire from the panel to the 'battery' (thru the 20A Signal fuse circuit), and a white wire (one of three) from the alternator. It should be one of those two. As to which plug that wire lives in, I have no idea.

The regulator/rectifier is not involved (other than that it also connects to the alternator with 3 white wires). One white from alternator goes only to rect/reg, one (the center one?) goes to rect/reg and tach, the third goes to rect/reg and lcd panel.

You can see the gang of wires coming out of the panel, follow that into the headlight bucket and see where that brown and that white plug in, and you might have found the problem.