A method for determining an error in the angular position measurement of a timepiece motor having one or more phases, including: detecting (3) each instant (14) when the value of one of the back electromotive forces is zero, storing (4) a time corresponding to each detected instant, measuring (5) several time intervals between two instants (14) detected in the same revolution of the motor, comparing (6) the measured time intervals to reference time intervals to deduce the reference intervals to which they correspond, and determining (7) an angular position measurement error if the measured intervals do not correspond to the expected reference intervals. The invention also relates to a method for correcting the angular position measurement. Also, a determination and correction system for implementing the methods and a timepiece including such a system.