'97 Suzuki Bandit 1200 Blue Wire Harness Question

Hello, I have been trying to get my backlite speedo, tach and fuel
gauge to work and I found that all the bulbs were blown. (bought the
bike used a few weeks ago) Anyway, I read online that sometimes a bad
connection can also be found in the blue wire connector in the
ferring. I found that there was a bad grey wire. I think that grey
wire is suppose to be suppling the power to the lights in the gauges
but there is no voltage even at the blue connector? Does anyone have
a service manual for a 1997 suzuki bandit who might be able to verify
that the grey wire is the supply and not the ground. And if so, where
might be the next place to check, possible the voltage regulator under
the seat?
Thank you very much for any help.
jesse