Contact detection device

A contact detection device comprising:

• an electrostatic capacitance sensor provided on a steering wheel of a vehicle, and configured to detect contact of a human body with the steering wheel;
• an estimation unit configured to estimate whether the human body is in contact with the steering wheel;
• a diagnosis unit configured to conduct a failure diagnosis related to the electrostatic capacitance sensor, based on a detection result of the electrostatic capacitance sensor in a case where the estimation unit estimates that the human body is in contact with the steering wheel and a detection result of the electrostatic capacitance sensor in a case where the estimation unit estimates that the human body is in no contact with the steering wheel;
• a determination unit configured to compare a detection result of the electrostatic capacitance sensor with a threshold value to determine whether the human body is in contact with the steering wheel;
• and
• a change unit configured to change the threshold value when the diagnosis unit determines that a failure related to the electrostatic capacitance sensor occurs.