The present disclosure related to a robotic working tool100comprising a controller110and at least a first and at least a second magnetic sensor arranged to sense a magnetic signal. The controller 110is configured to detect a first magnetic signal; determine a signal strength of the detected first magnetic signal;determine if the signal strength of the detected magnetic signal is above or below a threshold value, and if the signal strength is above the threshold value, accept signal detection input for the first magnetic signal from a first set of sensors, and if the signal strength is below the threshold value, accept signal detection input for the first magnetic signal from a second set of sensors, wherein the second set of sensors is a subset of the first set.The disclosure also relates to a method for use in the robotic working tool and a computer readable medium for carrying computer instructions that when loaded into a controller of a robotic working tool, cause the robotic working tool to operate according to a method.