Yureka has recently got updated with the CyanogenMod 12 update and there are many issues which users are complaining about after this update. I have earlier updated about the list of Problems in Yu Yureka. And the Screen turning black during a phone call is one of the most common problems being reported by users across various forums and I personally faced this issue making it really frustrating.
Updated on May 27th 2015
Why is the display turning Black during calls in Yu Yureka?
After some research I found that this is being caused due to problem with the calibration of Proximity Sensor because of which the device is not able to know when you are moving your phone away from your face or ear, and hence the screen is remaining black.
Steps to Fix Blank or Black Screen Bug in Yu Yureka:
As we now know that it is being caused by the Proximity sensor problem there is a simple process with which you can calibrate your proximity sensor manually which will set things right. Follow the steps given below to manually calibrate the Proximity Sensor.
Tap on Phone app and open Keypad or DialPad
Now you have to type in or enter *#*#7769#*#* and press call
You will be taken to the Proximity Calibrate Menu or Info, now tap on Start
The Calibration process with start automatically and you have to wait till the Calibration Good text appears in Green.
Now you can tap on Stop to end the calibration process and Exit the Calibration process.
Tighten Screws to fix proximity sensor issue in Yu Yureka:
This method has been updated by some users who have tried some methods like pressing hard on the proximity sensor area which has made the screen return back to normal. This is because sometimes the screws are not tight enough and if you tighten the screws behind the proximity sensor region the problem has been solved as mentioned by many users.
Open the back panel on your Yu Yureka
As shown in the image you have to tighten the two Screws which are circled in Red
Use a small screwdriver which we are getting in the market
After this try and make a call and check if the problem is fixed and then you can close the back panel. Make sure that you try calibrating the proximity sensor first and then tighten the screws too if possible.
This is the one solution which worked for me and make a note that this method is for users who have updated their Yureka OS to CM12. If you are still facing the same issue with your device then make sure that the Screen guard is not covering the proximity sensor and there is no dust over the sensor. This step has been useful to manually calibrate the proximity sensor which was not properly calibrated after the CM12 update was installed. This same problem was seen earlier to CM12 as well but was not this chronic and which should have been solved after the CM12 update just got worse. Do let me know if the fix worked and if any other method has helped you solve the bug in the comments section.