An imaging device comprising: a first control line (VMAL); a first voltage generator that applies a first voltage to the first control line (VMAL); a first signal line (SGL); a plurality of pixels that applies a pixel voltage to the first signal line (SGL); a first dummy pixel (P3A) that applies a voltage corresponding to the first voltage of the first control line (VMAL) to the first signal line (SGL) in a first period, wherein the first period includes a period within a blanking period; a converter including a first converter (ADC) that performs AD conversion on a basis of a voltage of the first signal line (SGL) in the first period to generate a first digital code; a diagnosis section that performs diagnosis processing on a basis of the first digital code, wherein the diagnosis section performs the diagnosis processing through confirming whether or not the first digital code comprises a code within a predetermined range corresponding to the first voltage; a first coupling section, wherein the first control line (VMAL), the first signal line (SGL), the plurality of pixels, and the first dummy pixel (P3A) are formed in a first substrate, at least a portion of the first converter (ADC) is formed in a second substrate, the first coupling section electrically couples the first signal line (SGL) in the first substrate and the first converter (ADC) in the second substrate to each other, and a second coupling section, wherein the first voltage generator is formed in the second substrate, the second coupling section electrically couples the first control line (VMAL) in the first substrate and the first voltage generator in the second substrate to each other, and the diagnosis section performs diagnosis processing related to the first coupling section and the second coupling section. a first control line (VMAL); a first voltage generator that applies a first voltage to the first control line (VMAL); a first signal line (SGL); a plurality of pixels that applies a pixel voltage to the first signal line (SGL); a first dummy pixel (P3A) that applies a voltage corresponding to the first voltage of the first control line (VMAL) to the first signal line (SGL) in a first period, wherein the first period includes a period within a blanking period; a converter including a first converter (ADC) that performs AD conversion on a basis of a voltage of the first signal line (SGL) in the first period to generate a first digital code; a diagnosis section that performs diagnosis processing on a basis of the first digital code, wherein the diagnosis section performs the diagnosis processing through confirming whether or not the first digital code comprises a code within a predetermined range corresponding to the first voltage; a first coupling section, wherein the first control line (VMAL), the first signal line (SGL), the plurality of pixels, and the first dummy pixel (P3A) are formed in a first substrate, at least a portion of the first converter (ADC) is formed in a second substrate, the first coupling section electrically couples the first signal line (SGL) in the first substrate and the first converter (ADC) in the second substrate to each other, and a second coupling section, wherein the first voltage generator is formed in the second substrate, the second coupling section electrically couples the first control line (VMAL) in the first substrate and the first voltage generator in the second substrate to each other, and the diagnosis section performs diagnosis processing related to the first coupling section and the second coupling section.