A load drive circuit that causes a switching element connected between a positive electrode of a direct current power supply and an output terminal to carry out a switching operation, thereby driving a load connected to the output terminal, the load drive circuit further including: a constant current element connected in parallel with the switching element; a resistor connected between the constant current element and the negative electrode of the direct current power supply; and an open load detection circuit including a load trouble detection circuit including the constant current element and a supply fault detection circuit including the resistor, wherein the open load detection circuit is configured to detect an opening of the load when the voltage (V out) of the output terminal is higher than the value of a first threshold voltage (V th (n)) and lower than the value, which is obtained by subtracting a second threshold voltage (V th (p)) from the voltage (V cc) of the direct current power supply, when the switching element is in an off-state, and wherein the supply fault detection circuit is configured to detect a supply fault when the voltage (V out) of the output terminal is higher than the value, which is obtained by subtracting the second threshold voltage (V th (p)) from the voltage (V cc) of the direct current power supply, when the switching element is in an off-state, wherein a supply fault is a condition in which a positive electrode of the direct current power supply and the load are short circuited, or there is an extremely low resistance value, and wherein the load trouble detection circuit includes a switch element having the first threshold voltage (V th (n)) and is configured so as to detect that the voltage (V out) of the output terminal is higher than the value of the first threshold voltage (V th (n)) in response to the switch element being turned on, and wherein the constant current (I d) from the constant current element and a value (R r) of the resistor are set so that the switch element is turned on in response to the load opening. a constant current element connected in parallel with the switching element; a resistor connected between the constant current element and the negative electrode of the direct current power supply; and an open load detection circuit including a load trouble detection circuit including the constant current element and a supply fault detection circuit including the resistor, wherein the open load detection circuit is configured to detect an opening of the load when the voltage (V out) of the output terminal is higher than the value of a first threshold voltage (V th (n)) and lower than the value, which is obtained by subtracting a second threshold voltage (V th (p)) from the voltage (V cc) of the direct current power supply, when the switching element is in an off-state, and wherein the supply fault detection circuit is configured to detect a supply fault when the voltage (V out) of the output terminal is higher than the value, which is obtained by subtracting the second threshold voltage (V th (p)) from the voltage (V cc) of the direct current power supply, when the switching element is in an off-state, wherein a supply fault is a condition in which a positive electrode of the direct current power supply and the load are short circuited, or there is an extremely low resistance value, and wherein the load trouble detection circuit includes a switch element having the first threshold voltage (V th (n)) and is configured so as to detect that the voltage (V out) of the output terminal is higher than the value of the first threshold voltage (V th (n)) in response to the switch element being turned on, and wherein the constant current (I d) from the constant current element and a value (R r) of the resistor are set so that the switch element is turned on in response to the load opening.