Battery drain in 1987 Dodge Xplorer

From : darlington

Q: can someone suggest how we can find whats putting a .2 amp drain on the front battery of a dodge xplorer van its not a defective battery as this is the 3rd one and all have been drained 24/7... killing two of them. we pulled some fuses - no joy. we shut everything off - no dice. we looked for underhood lights etc.... nada. can somone shed some light on this problem there are 2 batteries in the back that i believe are charged when this van is being driven. suggestions ideas .