My Dell off brand power adapter could not provide power to Dell laptop. I decided to take a look inside. But there were no screws or tabs in the adapter. It was glued together. Inserted two screw drivers into power supply’s strap slot, I pried open the power adapter. One of the power input legs was loose probably due to excessive vibration during travel. I soldered it and this fixed the problem. Instead of glue the adapter back, I used two black cable ties to strap it close. It looked fine when I wrapped wires back onto power adapter.
