The failure of Dongling coffee machine 5400 may occur in the following situations:

1. The coffee machine cannot be turned on normally. This situation may be because the power socket is not plugged in properly or the socket is faulty. It is recommended to replace the socket or contact a professional for maintenance.

2. The coffee machine is not heated in time. This situation may be due to the failure of the heating rod and the need to replace the heating rod.

3. The coffee machine is not flowing smoothly. This may be because the filter is blocked or there is no water in the water tank. Please clean the filter or fill it with water before using it.

4. The coffee machine is leaking. This situation may be due to loose connecting fittings or aging sealing rings, which need to be reinstalled or replaced.

5. The coffee machine automatically shuts down. This situation may be due to the set automatic shutdown time or the failure protection of the coffee machine. It is recommended to check the settings or contact a professional for maintenance.

In a word, for the failure of Dongling coffee machine 5400, we can try to make a preliminary investigation through the above methods first. If it cannot be solved, we should contact professionals for maintenance or replacement of parts. In addition, you should also pay attention to the correct operation method and regular cleaning and maintenance when using the coffee machine at ordinary times to avoid failure.