The present disclosure discloses an array substrate, a display device and a fault repair method for an array substrate, and belongs to the field of display technology. The array substrate includes a pixel array, a gate driver array including a plurality of gate driver units and configured to output drive signals to pixels in the pixel array, and a repair line overlapping with and insulated from the gate driver units, wherein the repair line is configured to be coupled to the failed gate driver unit and transmits a repair signal to cause the failed gate driver unit to output a normal drive signal, when any gate driver unit fails. The added repair line can realize the function of repairing when the gate driver unit fails, and improve the production efficiency of the array substrate.