GE LOGIQ E9 ultrasound machine frequent crashes

Failure phenomenon

GE LOGIQ E9 color Doppler ultrasound frequently crashes after turning on.

Failure analysis

This fault is a startup fault. First, it is necessary to determine whether the fault is at the front or back end of the system.

Open the BEP shell, turn it on, and find that the rear power indicator shows the following: PS-ON and 5 V stdby LED indicators are on, other indicators are off. It can be seen that +5 V STB has output and PS-ON has action, but there is no +48 V voltage directly output by the main power supply. The reasons for this phenomenon may be:
① The main power supply fails;
② The +48 V load has an overcurrent short-circuit phenomenon.

After disconnecting the +48 V load, the fault remains. It is judged that the fault is caused by poor main power supply. For further confirmation, after the main power supply was removed and tested separately, it was found that the main power supply was damaged and there was no +48 V output. After replacement, the fault was eliminated.