That's not a center piece of wood, it's just the pith of that particular piece of wood.
Those old AB2 often has the bluEQube in it. The switch closer to the neck turns it on/off (it's a mid shift). The switch closer to the bridge is the active/passive switch. The knobs, going from neck to bridge, should be: Volume, Rotary pickup selector, Bass (boost only IIRC), Treble (boost only IIRC).
If the Active/Passive switch was causing it to "kill", I'd suspect dead batteries first. Easy enough to test. If the bluEQube switch was acting as a kill, that's unfortunate, but also easy to test.