Common Faults and Repair Methods for Ultrasound Diagnostic Equipment

The ultrasound diagnostic device is a common examination method in clinical diagnosis and treatment, and its usage directly affects the accuracy of the examination. As maintenance personnel, one should have a precise understanding of the working principles, components, functions, technical parameters, and operating procedures of the ultrasound diagnostic device. It is also necessary to have some knowledge of the various faults that may occur during the use of the ultrasound diagnostic device and to carry out effective repairs in a timely manner. The components of the ultrasound diagnostic device include the display screen, main unit, probe, and image workstation. Its working principle relies on the transmission and reflection of ultrasound waves to examine the morphology and function of relevant tissues and organs in the human body; this examination is based on the premises of pathology and human anatomy, and it can accurately display the morphological and pathological changes of internal tissues in the human body, making it a widely used and effective examination method in clinical practice.

Fault One

Fault Phenomenon:

After turning on, the display screen is black, and the power indicator light on the display is yellow.

Fault Analysis and Elimination:

If the power indicator light on the display is yellow, it indicates that the main unit is receiving power. First, turn off the device, unplug the power plug, and use a multimeter to measure the voltage to determine if the AC power supply is stable. If the measured AC voltage is 220V, it indicates that the voltage is stable. If the screen remains black after powering on, it indicates a fault with the display; if the power is connected and the software interface opens, but there are occasional black screens in the software image area, with no observation of the ultrasound diagnostic system starting normally, it can be determined that the main unit system is not starting and the display itself is not faulty. The cause of this latter situation may be a fault in the central processing unit (CPU), memory bar, motherboard, or expansion card.

Repair Method:

(1) Disconnect the power and remove the side cover of the main unit;

(2) After connecting the power, turn on the device and check if the CPU fan is functioning normally and if there are any abnormalities; (3) After shutting down, disconnect the power, remove the memory bar, and if oxidation is found on both sides of the metal contacts of the memory bar in the motherboard slot, it may be due to looseness in the memory bar slot or excessive dust accumulation, leading to poor contact and preventing the system from starting normally. Remove the memory bar, gently erase the oxidized parts with an eraser, and reinsert the memory bar into the slot to start normally.

Fault Two

Fault Phenomenon:

After powering on, the system enters the inspection interface, but there is no probe sector image, displaying artifacts.

Fault Analysis and Elimination:

If the normal startup is observed upon powering on, but artifacts appear in the probe sector position image in the inspection interface, showing a higher right and lower left issue, this is usually due to a fault in the ultrasound probe, video processing, video format conversion, or system monitoring (RM) control and docking issues, or it could be a fault in the motherboard.

Repair Method:

Try replacing with a probe of the same model and check again. If the fault is eliminated, it indicates a probe issue, and the probe can be replaced; if the fault persists, it indicates a problem with the visual recognition system or the main unit. During troubleshooting, it is noted that there is a wide data cable connecting the visual recognition system and the motherboard, which facilitates front-end and back-end communication. It may be a contact issue between the visual recognition system and the data cable. Remove the data cable for dust cleaning, check for any damage, and ensure good contact after reinserting it before powering on to observe if the probe sector position image displays normally.

Fault Three

Fault Phenomenon:

The system cannot enter the system after powering on, remaining stuck on the startup screen, or freezing occurs.

Fault Analysis and Elimination:

Some ultrasound diagnostic devices often experience irregular freezing issues during actual use, requiring a restart of the main unit. If the system cannot be entered after multiple restarts and remains stuck on the startup screen, the causes for this fault can be numerous, including issues with the operating system software, motherboard, CPU, hard drive, memory, or expansion cards.

Repair Method:

Based on past repair experience, hardware contact issues may also cause freezing. The hardware components in the ultrasound diagnostic device’s motherboard can be disassembled and cleaned, and after reinstalling, it can be observed that the device starts normally, thus eliminating the fault.

① Restart the ultrasound diagnostic device

This repair method does not have technical requirements and is applicable to general cases where system faults are caused by the operator’s insufficient understanding of the instrument, lack of knowledge, or unfamiliarity with system operations. Thus, technicians can first disconnect the power to restart and see if it can eliminate the fault.

② Observe the ultrasound diagnostic device

During the repair of the ultrasound diagnostic device, one should first observe the operational flow, checking its operational status and the actual operating environment of the hardware. After a comprehensive observation and analysis, repair personnel can more quickly locate the fault cause and conduct repairs promptly.

③ Tap the ultrasound diagnostic device

If during repairs, it is suspected that the fault may be due to poor contact between instrument components, the device can be gently tapped. Using a rubber stick to tap on the components can create appropriate vibrations or distortions to identify the fault point and then proceed with repairs.

④ Clean the ultrasound diagnostic device

Many faults occur because the instrument has been stored for a long time without thorough cleaning, leading to dust accumulation in the device, ultimately affecting its normal use. Therefore, during the repair of the ultrasound diagnostic device, it is also essential to ensure proper cleaning of the equipment, focusing on components that are prone to dust accumulation. After removing the dust, check if the fault has been eliminated; if not, proceed to the next repair step.

⑤ Replace the ultrasound diagnostic device

For faulty components, replace them with components of the same model and check if the fault can be eliminated. When replacing components, follow the principle of starting with simple parts before moving to more complex ones. Since the replacement process may lead to secondary faults in the ultrasound diagnostic device, caution must be exercised during the replacement operation.

⑥ Check the ultrasound diagnostic device

If it is determined that there is a circuit fault during repairs, a comprehensive check should be conducted on the main unit circuit. Typically, methods such as resistance measurement, substitution method, current detection, and waveform observation can be used. The resistance measurement method analyzes the specific location of circuit faults based on the resistance values, subsequently identifying which component is faulty; the substitution method generally involves replacing each component in the faulty unit; during the substitution process, it is essential to ensure that the components used have the same performance parameters; the current measurement method combines voltage levels to analyze the operational phenomena of the ultrasound diagnostic device’s unit circuit, pinpointing the faulty component; finally, waveform observation relies on an oscilloscope to measure signal waveforms, determining the location of faults based on the specific working conditions of the unit circuit.

In summary, the ultrasound diagnostic device is a commonly used examination tool in clinical practice, and ensuring its normal operation is of significant importance for medical activities. Therefore, in practical operations, it is essential to actively strengthen the fault analysis of ultrasound diagnostic devices, conduct timely repairs, and pay attention to preventive maintenance of ultrasound diagnostic devices to reduce the occurrence of faults during use.