Почему ноутбук не включается. Диагностика платы. Находим и устраняем причину!

Introduction

This tutorial provides a step-by-step guide for diagnosing and repairing a laptop that does not turn on, specifically focusing on the ASUS K53SV model. It addresses common issues, including the absence of standby voltages, and offers practical advice on troubleshooting the charging controller and using a multimeter for diagnosis.

Step 1: Identify Symptoms of the Issue

• Confirm that the laptop is completely unresponsive to the power button.
• Check for any signs of power like fan movement, LED indicators, or sounds.
• Understand that the problem may often be referred to as "the laptop does not start," which can be misleading.

Step 2: Check for Standby Voltages

• Use a multimeter to measure the standby voltages:
  • Look for 3.3V and 5V outputs.
  • If these voltages are absent, proceed to the next step.
• Note that the issue may not lie in the switching power supply controlled by the RT8206 PWM controller.

Step 3: Diagnose the Charging Controller

• Focus on the BQ24740 charging controller:
  • Investigate why it may have malfunctioned, as it is crucial for the laptop's power management.
• If you do not have the schematic for the laptop, search for the datasheet for the BQ24740 to understand its function and pin configuration.

Step 4: Utilize a Multimeter for Testing

• Use the multimeter to test the following:
  • Continuity between relevant pins on the BQ24740.
  • Voltage levels at various points to identify discrepancies.
• Common pitfalls:
  • Ensure the multimeter is set to the correct mode for voltage or continuity testing.

Step 5: Repair or Replace Faulty Components

• If the BQ24740 is confirmed faulty:
  • Consider replacing it if you have the necessary soldering skills and equipment.
  • If not, consult a professional repair service.
• Double-check all connections after replacement.

Step 6: Reassemble and Test the Laptop

• Carefully reassemble the laptop, ensuring all components are correctly connected.
• Power on the laptop to check if the issue is resolved.
• If the problem persists, further diagnosis may be necessary.

Conclusion

In this tutorial, we covered the steps for diagnosing a non-responsive ASUS K53SV laptop, focusing on the importance of checking standby voltages and diagnosing the BQ24740 charging controller. Should the problem continue after these steps, consider seeking professional repair services or further technical resources.