The present invention relates to a method for performing a logic built-in self-test (LBIST) on an electronic circuit with a plurality of logic circuits (18, 20, 22, 24) and storage elements (14, 16) connected serially to a number of LBIST stumps (10, 12) between a pseudo-random-pattern generator (26) and a multiple-input-signature register (28), wherein at least one constrained logic circuit (18) requires constrained values as input signals. Said method comprises the following steps: scanning the LBIST stumps (10, 12) with the pseudo-random-pattern generator (26), deactivating the multiple-input-signature register (28), performing a functional update in order to propagate legal values into those storage elements (16), which require constrained values, activating or resetting (51) the multiple-input-signature register (28), and setting or programming a start value in a counter (42) for activating a loop back circuit (34) in order to avoid an overwriting of the well-constrained values in the storage elements (16).