A method for detecting non-uniform and uniform deterioration states in a suspension member arrangement for an elevator, the suspension member arrangement comprising at least one suspension member having a first and a second group (24a, 24b) of electrically conductive cords, wherein first ends (25a, 25b) of the first and second group (24a, 24b) of electrically conductive cords are electrically connected to an alternating voltage generator arrangement comprising a first voltage generator (G 1) for applying a first alternating voltage U 1 to a first end of the first group of cords of the suspension member and a second voltage generator (G 2) for applying a second alternating voltage U 2 to a first end of the second group of cords of the suspension member, and wherein second ends (27a, 27b) of the first and second group (24a, 24b) of electrically conductive cords are electrically connected to each other via a neutral point at which electrical resistances to the first voltage generator (G 1) and to the second voltage generator (G 2), respectively, are same in a non-deteriorated state of the suspension member arrangement; and wherein first and second electrical resistors (R a, R b) are arranged between the neutral point and the second ends (27a, 27b) of the first and second group (24a, 24b) of electrically conductive cords, respectively; the method comprising: - applying the first alternating voltage U 1 to the first end of the first group of cords of the suspension member and applying the second alternating voltage U 2 to the first end of the second group of cords of the suspension member; - determining a neutral point voltage U n between the neutral point and an electrical reference potential; - determining a difference voltage U d between a first difference measurement point, located between the second end of the first group of electrically conductive cords and the first electrical resistor (R a), and a second difference measurement point, located between the second end of the second group of electrically conductive cords and the second electrical resistor (R b); - determining the deterioration state based on both the determined neutral point voltage U n and the determined difference voltage U d. the suspension member arrangement comprising at least one suspension member having a first and a second group (24a, 24b) of electrically conductive cords, wherein first ends (25a, 25b) of the first and second group (24a, 24b) of electrically conductive cords are electrically connected to an alternating voltage generator arrangement comprising a first voltage generator (G 1) for applying a first alternating voltage U 1 to a first end of the first group of cords of the suspension member and a second voltage generator (G 2) for applying a second alternating voltage U 2 to a first end of the second group of cords of the suspension member, and wherein second ends (27a, 27b) of the first and second group (24a, 24b) of electrically conductive cords are electrically connected to each other via a neutral point at which electrical resistances to the first voltage generator (G 1) and to the second voltage generator (G 2), respectively, are same in a non-deteriorated state of the suspension member arrangement; and wherein first and second electrical resistors (R a, R b) are arranged between the neutral point and the second ends (27a, 27b) of the first and second group (24a, 24b) of electrically conductive cords, respectively; the method comprising: - applying the first alternating voltage U 1 to the first end of the first group of cords of the suspension member and applying the second alternating voltage U 2 to the first end of the second group of cords of the suspension member; - determining a neutral point voltage U n between the neutral point and an electrical reference potential; - determining a difference voltage U d between a first difference measurement point, located between the second end of the first group of electrically conductive cords and the first electrical resistor (R a), and a second difference measurement point, located between the second end of the second group of electrically conductive cords and the second electrical resistor (R b); - determining the deterioration state based on both the determined neutral point voltage U n and the determined difference voltage U d. - applying the first alternating voltage U 1 to the first end of the first group of cords of the suspension member and applying the second alternating voltage U 2 to the first end of the second group of cords of the suspension member; - determining a neutral point voltage U n between the neutral point and an electrical reference potential; - determining a difference voltage U d between a first difference measurement point, located between the second end of the first group of electrically conductive cords and the first electrical resistor (R a), and a second difference measurement point, located between the second end of the second group of electrically conductive cords and the second electrical resistor (R b); - determining the deterioration state based on both the determined neutral point voltage U n and the determined difference voltage U d.