Is this both pickups?
If it was just the neck, I'd say red/yellow might be the ends of the coil, the sheath might be ground for the cover...
Actually, the baseplate on the bridge might be the sheath on the other?
Are you looking at the control cavity end only? I'd be tempted to whip the pickups out (pain for the bridge) and see what they're connected to...
Alternatively, wait til someone who knows what they're talking about comes along on here... :lol: