Question for you Oldsmobile techs, 99 Aurora not starting and having a weird electrical issue. There'* no lights of any kind, dash interior and exterior. Hooked up cables from under the hood and nothing but a relay clicking, hooked up directly to the battery and everything worked. But once the car started all the lights went out, gauge cluster stopped working,. But the car stayed running. Tried turning on the signal and the car bogged down. Assuming it was running off the battery until it died. The battery is brand new along with the Alternator, security system has been bypassed. Any ideas? I'm assuming it'* something between the under the hood connection and battery but clueless. Any help is appreciated

It could be the body control module it controls most of what your talking about.
Most the time its located DS near the parking brake.
It will have like 3 or 4 plugs connecting to it with a bunch of wires.
Some part stores can order you one pre programed as it control'* the theft system
Most will say it has to be flashed at a dealer but that'* not total true.
As far as getting one out of a junk yard some will say it will work if you match up the part# on the out side some will say you need a TECH 2 to program it.
My own experience at the time with out a TECH 2 after the relearn process was done
the car would start but anti lock light was on.
The relearn process should be here in the forum.