Repair Topcon 17" LCD for 10 cents

The circuit board with Genesis GM 5120 chip. Initially I thought this chip is overheated and faulty. But temperature test did not reproduce the problem.



The burnt SMD reistor is replaced with a 0.5W 1k resistor.


The burnt resistor.


High voltage circuit on the right. Control circuit at the center.

This is the worst LCD with poor quality control I ever have. It starts showing abnormal green lines over white area randomly after powering on for 30-60 mins. Since it is bought for over 6 months, it was sent to the repair centre for checking. After sending to the customer services for 3 times over 3 months, they still claim the LCD has no problem. The problem gets worst and worst and becoming completelty white screen after 3 hours operation.

Opening up the circuit board with careful inspection, on of the capacitor show some buldging, yet no leaking. A 10k resistor near a transistor seems blown off.

The SMD 103 10k resistor was fixed with a larger one, but it works. Testing for 48 hours show that the operation is successful.