How to Fix iPhone 6S Plus Half Black Screen/Backlight Failure, Case 2 | Chip Level Repair


Half black screen/backlight problem is common in iPhone 6 Plus, 6s Plus, 7 Plus and 8 Plus, because the backlight circuits of these models have two sets of boost circuits. One boost circuit control left half backlight and the other one control right half backlight. If one set is failed while the other is still working, half of the screen will become black. in this article we will share how to troubleshoot iPhone 6S Plus backlight/screen half black and fix it with jumper wire, hope you enjoy our sharing.

Step 1 Function Test

Check the motherboard, and we defect the sign the water damage, buckle the motherboard with a screen assembly and connect to power, when boot it up, half of the screen gets black and the other half lights on normally.

Step 2 Troubleshooting

Place the motherboard under the microscope, measure the diode resistance of the display connector, the display connector pin 6 is measured no diode resistance, while the diode resistance of the. FL4211 is measured normal.

Step 3 Diagnosis

The line between FL4211 and display connector pin 6 end is measured open circuit. As the display connector pin is found damaged, and the display connector pin 6 is measured no diode resistance, however, when hard press the display connector pin 6, the diode resistance showed normal. For this situation, we will replace the display connector then make jumper wire.

Step 4 Repairing

Add some solder flux paste on the display connector, then use the hot air gun to remove the display connector. Add tin on the display connector soldering pads, solder a jumper wire on the FL4211. Apply a thin layer of UV curable solder mask on the jumper wire, then cure by the UV curing light for about 1 minute.

Add solder flux paste, replace a new good display connector, then solder the jumper wire to the display connector pin 6.

Step 5 Reassemble & Test

Assemble the motherboard, connect to power and boot up the iPhone. All function is tested normal, repair completed.

Please refer to below detailed video:

Connect with us

On FacebookLinkedInTwitterYouTubeInstagram

Questions are utterly welcome!

Tools and Materials Used in This Video:

DC Power Supply



Motherboard fixture



PCB cleaner

Cleanroom wipes

Hot air gun

Solder flux paste

Soldering iron

Cooper wire

UV curable solder mask

UV curing light

Leave a Reply

Your email address will not be published. Required fields are marked *