In the context of maintenance testing and diagnosis of faulty boards, a functional FSM (Finite State Machine)-based model for mixed-signal board has been introduced. The board is broken down into interconnected functional blocks. Each block has an associated functional model which describes its behavior and a test model which specifies how the block can be efficiently tested. A test model for a block is created by merging its functional model and a chosen test strategy. The board checking consists in testing each block individually using its test model and functional models of other blocks. Test patterns for a component are generated by covering the transitions of its test model and propagation to primary inputs/outputs through functional models of other blocks. The board test data set is built by using the test patterns for all the blocks of the board. The current improvement of the method deals with basic signals.