Gauges coming on when headlights turned on

[Aussie-Parnelli]

Had a problem last night at racing
Car run fine until evening when I turned headlights on.
Car started misfiring and when I returned to pits the car continued to run when I turned key off
Turning the headlight off engine stopped.
Now when I turn lights on the instruments and warning lights illuminate
If I remove Fuse 67 eliminates problem, manual doesn't tell me much it goes to SJB but what is it used for
Strange never experienced this before
Any ideas

 

[Juice]

Water leak into SJB? That's a very odd combination of issues.