1. power failure: check whether the power plug and fuse are normal and whether there is any wire damage.
2. Controller failure: Check whether the power interface and communication interface of the controller are stable and whether the controller is connected correctly. If the connection is correct, you can try to restart the controller to solve the problem.
3. Sensor failure: Check whether the temperature sensor is properly connected and damaged. If there is a problem, you can replace the sensor to solve it.