Jammed dc motor detection method

An aircraft temperature control system comprising:

• a resistance temperature detector (RTD) a fan comprising:
• fan blades directed to blow air across the RTD when rotated, and
• a DC motor coupled to the fan blades and configured to rotatably drive the fan blades during operation of the DC motor;
• and
• a control assembly comprising:
• a microcontroller electrically coupled to the DC motor and configured to:
• derive a current variance of a current being provided to the DC motor,
• determine that the current variance has remained below a variance threshold for at least a duration of a time threshold, and
• output to an aircraft diagnostics system an indication that the fan is jammed based on the determination that the current variance has remained below the variance threshold for at least the duration of the time threshold.

A method of determining that a DC motor is jammed, the method comprising:

• determining a current being provided to a DC motor;
• deriving a current variance of the current being provided to the DC motor;
• determining that the current being provided to the DC motor has remained above a current threshold for a threshold amount of time;
• determining that the current variance has remained below a variance threshold for the threshold amount of time;
• outputting to an aircraft diagnostics system an indication that the DC motor is jammed based on the determination that the current variance has remained below the variance threshold for the threshold amount of time and that the current being provided to the DC motor has remained above the current threshold for the threshold amount of time.