In a solid-state image sensor in which an arbiter arbitrates a request, a failure point is identified. A plurality of pixels generates a request for requesting transmission of a predetermined detection signal, in a case where a predetermined event is detected. A test circuit outputs the request of each of the plurality of pixels as an output request in a case where a test is not instructed, and generates a plurality of new requests and outputs each as the output request in a case where the test is instructed. The arbiter arbitrates the output request. A communication circuit transmits the detection signal on the basis of an arbitration result of the arbiter. A failure determination unit determines whether or not the arbiter has a failure on the basis of the detection signal in a case where the test is instructed.