I think if this were my job ,I would be looking at a different approach.Firstly make sure you are starting with a fully charged battery,as a low voltage can cause various controllers to throw a wobbly.Carry out a global scan of all controllers to see if there any relevant fault codes .Disconnecting consumers and pulling fuses is counter productive,as vehicles using can network need a power supply to switch off.Use an amp clamp that is capable of accurate low current readings so that wires carrying power can be isolated without cutting/intrusion.You can pick out wires from behind the fuse box to see which is drawing power.Also may be an idea to get an "amp hound" which can check power draw across the back of a fuse.Also and non standard equipt fitted?
http://public.snapon.com/a_prodannouncements_us/EECT74_NPA.pdf