A control substrate for an indoor equipment of an air conditioner, the control substrate comprising: a substrate; a power-supply circuit that is mounted on the substrate and generates power used in the indoor equipment; a communication circuit that is mounted on the substrate and causes an outdoor equipment, connected to the indoor equipment, and the indoor equipment to communicate with each other; a first terminal block that is mounted on the substrate and includes a first wiring connector, a second wiring connector, and a third wiring connector; a second terminal block that is mounted on the substrate and includes a fourth wiring connector and a fifth wiring connector; a first pattern first pattern that is formed on the substrate and connects the first wiring connector and the power-supply circuit to each other; a second pattern that is formed on the substrate and connects the second wiring connector and the power-supply circuit to each other; a third pattern that is formed on the substrate and connects the second wiring connector and the communication circuit to each other; a fourth pattern that is formed on the substrate and connects the third wiring connector and the communication circuit to each other; a fifth pattern that is formed on the substrate and connects the fourth wiring connector and the communication circuit to each other; a sixth pattern that is formed on the substrate and connects the fifth wiring connector and the communication circuit to each other; a first switch that is provided in the third pattern and is capable of switching connection and disconnection between the second wiring connector and the communication circuit; a second switch that is provided in the fifth pattern and is capable of switching connection and disconnection between the fourth wiring connector and the communication circuit; and a switching assistant that is attached to either one of the first switch and the second switch and switches between a state where the second wiring connector and the communication circuit are connected to each other and a state where the fourth wiring connector and the communication circuit are connected to each other. a substrate; a power-supply circuit that is mounted on the substrate and generates power used in the indoor equipment; a communication circuit that is mounted on the substrate and causes an outdoor equipment, connected to the indoor equipment, and the indoor equipment to communicate with each other; a first terminal block that is mounted on the substrate and includes a first wiring connector, a second wiring connector, and a third wiring connector; a second terminal block that is mounted on the substrate and includes a fourth wiring connector and a fifth wiring connector; a first pattern first pattern that is formed on the substrate and connects the first wiring connector and the power-supply circuit to each other; a second pattern that is formed on the substrate and connects the second wiring connector and the power-supply circuit to each other; a third pattern that is formed on the substrate and connects the second wiring connector and the communication circuit to each other; a fourth pattern that is formed on the substrate and connects the third wiring connector and the communication circuit to each other; a fifth pattern that is formed on the substrate and connects the fourth wiring connector and the communication circuit to each other; a sixth pattern that is formed on the substrate and connects the fifth wiring connector and the communication circuit to each other; a first switch that is provided in the third pattern and is capable of switching connection and disconnection between the second wiring connector and the communication circuit; a second switch that is provided in the fifth pattern and is capable of switching connection and disconnection between the fourth wiring connector and the communication circuit; and a switching assistant that is attached to either one of the first switch and the second switch and switches between a state where the second wiring connector and the communication circuit are connected to each other and a state where the fourth wiring connector and the communication circuit are connected to each other.