How I Fixed My OnePlus 7 Screen Flicker Issue

Recently, my OnePlus 7 screen broke, and I decided to replace it. I first checked the price of an original display on the official OnePlus website, and to my surprise, it was ₹8,940—a cost I found far too high. To save money, I explored alternatives and visited Naza Market, where I found a second-hand AMOLED display in good condition at a much more reasonable price.

Testing the Screen Before Purchase

In the shop, I only checked the display on high brightness. It looked great — clear, sharp, and working fine. So, I went ahead and got it fitted into my phone. The Problem Appeared Later

The next morning, when I lowered the brightness in a dim room, I noticed something unusual:

• The screen started flickering heavily. 
• At mid brightness, it was still usable. 
• At the lowest brightness, the display almost wiped out and became very unstable. 

At first, I thought it was just a software glitch, but then I realized it was something else. 

Why This Happens (AMOLED + PWM Flicker) 

The OnePlus 7 uses an AMOLED screen, and many AMOLED panels rely on PWM (Pulse Width Modulation) to control brightness. 

• At 100% brightness, pixels stay on all the time. 
• At 50% brightness, they blink on and off very quickly. 
• At 10% brightness, they’re off most of the time and only flash on briefly. 

Normally, this flicker is too fast for our eyes to notice. But on aged or second-hand panels, the flicker becomes visible as lines, shimmer, or full-screen flickering. That’s exactly what happened to me. 

How I Fixed It (Enabling DC Dimming with ADB) 

1) Turn on Developer Options

• Settings → About phone → tap Build number 7 times → go back.

2) Enable USB debugging

• Settings → Developer options → toggle USB debugging ON → allow the prompt.

3) Prepare ADB on your PC

• Install ADB (Android Platform Tools) on your computer.
• Connect your phone via USB → in a terminal run:

adb devices

• Tap Allow on the phone if asked.

4) Launch the hidden DC Dimming switch

Run this single-line command:

 adb shell am start-activity -a
    oneplus.intent.action.ONEPLUS_LAB_FEATURE_DETAILS -e oneplus_lab_feature_key
    oneplus_dc_dimming_value 

5) Enable DC Dimming

• A hidden DC Dimming page opens on the phone → toggle it ON.

6) Reboot

• Restart the phone to apply it.

7) Result

After reboot, low-brightness flicker is greatly reduced, and the phone is much more comfortable to use in the dark.

You might also like: Learn Mobile Repairing from Scratch

Conclusion

Replacing a OnePlus 7 screen with a second-hand AMOLED panel can be cost-effective, but it may introduce low-brightness flickering due to PWM. Thankfully, enabling DC Dimming via the hidden OnePlus feature effectively reduces this flicker, making the display comfortable to use at all brightness levels. If you’re considering a screen replacement, testing for flicker and knowing this fix can save you both money and frustration.