the "normal" passive drain would not kill battery in 2 days if it was fully charged on Saturday, can you get a DVM in series with battery, with ignition off, but FIA isolator,if fitted, in on position, to measure passive current drain, would expect iro 250 - 300 mA which would take around 10+ days to flatten battery
Have you checked electrolyte is up to top of cells, has it ever been completely flattened in the past, is it original battery - so 3 years old
Tim
Edited by - tbird on 28 May 2012 22:50:53