Fast fix or Samsung j7 back lights jumper ways are here. But before to continue, Some useful tricks for this issue. When the back lights are stop working. That mean user could not dial or use cell phone in the night. At the sun display show but in the dark there is no light. Issue comes from the faulty or damaged led one or more. Lights controller chip may harm and stop working. There is missing connection from the PCB to Connector. Any way see the diagram below here to fix the issue of. Samsung j7 back lights jumper ways.
Above pic will show you the 4 lines of the Samsung j7 back lights. Before working blindly please check and trace the missing point only. Clean the connector first the apply these jumpers with good quality jumper wire. There on the other side The j7 back lights controller chip to the connector side of the display. You can make a jumper. For the perfect success try to testing with check meter for the volts and lines connection. Many times on my lab. I see the only one point is missing. The Positive volts from the chip to connector. When i put this jumper directly handset j7 back lights are start working. Every electronics faults are differents from their location. It totally depend on your batter understanding with the diagram.
What to do next for j7 back lights problem.
Open the display panel with extra care. Find the Lights lamp at the panel. Make a direct jumper same as diagram above here. Do not jumper on the Connector. Just same from the panel lights to the controller chip points. Do not attach the direct battery volts on the lights points.
Lights may harm, Lights are on when battery inserted, lights on without powering the phone. cell phone is shorted. So there for There is the some other reasons behind that issue. At last final testing. After a jumpering, No Luck. Start normal heating lights controller chip, No Luck. By changing lights, No luck. By changing light controller chip, No luck. Check the positive volts at the in point of Chip, No Luck.
Let we shoot with other ways. Connect the panel on other working board. Panel is working fine that mean conform. The problem with PCB. That ways test the volts on connector and test the resistance near the lights controller chip. Hope you will now happy with success. For more inquire please feel free to comments at our job. Thanks for visit on fixphoneonline.com.