A voltage detection apparatus is configured to detect a voltage value applied to a first or second current path of a heater. The voltage detection apparatus detects a first period during which the voltage value of the first or second current path exceeds a threshold voltage as well as a second period during which electric power is supplied to the first current path or the second current path to control the electric power supplied to the first and second current paths. The voltage detection apparatus uses a detection result to detect a state where over-power is supplied to the heater.