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Apologies if this has been raised before, I have tried to check the other threads but haven't found the same problem.
I discovered when I called my voicemail that the screen on my nokia lumia 800 goes black as soon as I press 'call' - it means I can't press any of the buttons to get my messages or delete/save/etc, and the only thing I can do is then to hold the power button until the phone switches itself off. I then tried a call to my landline, and it does the same thing.
Has anyone else had this problem, and if so, have you found a solution? I don't know if I am doing something wrong.
It sounds like the sensor which switches off the screen when you hold the handset to your ear to avoid accidental contact may be faulty in some way or the phone is not acknowledging when it is moved away.
Can you try backing up the handset and restoring factory settings for me to clear any software glitch which may be occurring?
I'd also suggest ensuring that you have the latest available firmware version.
If the issue persists and you've had the phone for less than seven working days then you can arrange to swap it for a replacement. Alternatively you can try a warranty repair after this point to allow our teams to examine and fix the fault.
Thank you, Dave.
Sadly, that hasn't helped - I have had it for more than 7 days, so will see about getting it repaired under the warranty.
Could I ask do you have a case or screen protector on the phone which could be effecting th operation of the sensor?
Sorry, John - have only just seen this - but no, I don't have a screen protector. I did read that some people had solved the problem by removing the screen protector, or the appropriate corner of the protector, but I don't have one. Every so often the screen flashes on, but very rarely, and only for a split second. I can't be without my phone just at the moment, so I will have to wait to try to sort it out, but I will go into my nearest Vodaphone shop and see what they suggest. Having done some research, it does seem to be a fairly common problem. It's a shame - I really love the phone in every other way, but this is a big disadvantage. I have a two year contract, so I need to find a way to make it work!
In that case please can you test the proxmity sensor, this should help diagnose.
"Your can check if he sensor works correctly by going to diagnostic tools (if not available dial ##634#) and select the proximity test. You will see a yellow circle. When you put your hand over the sensor, which is in the left top corner of the Lumia 800, the circle will turn green until you remove your hand. If you are still stuck in "Detected" mode or it does not happen as described, please go to a Nokia Care point to have your device checked."
(Taken from Nokia Support Discussions)
Please let me know the results.
Many thanks for this, John. The circle was already green, not yellow, and remained green, so I am clearly stuck in 'detected' mode. I will go to a Nokia Care Point as suggested. Thanks again!
Hmm, except that there isn't a Nokia care point anywhere near me! Will go to my nearest Vodafone centre and see what they suggest.
Really don't understand why Vodafone only give you seven days to report faults...if they supply a faulty phone, they should replace it.
Hello. I have the Nokia Lumia 800, and i have the same problem. I have had a screen protector and case on there but i have taken them off, it still stays black when i call people. I tried the proximity test and the circle stayed green and said detected. What does this mean? Thank you
If the circle stays green when you move your hand away it means the proximity detector isn't registering this and thinks it's still covered.
This means that when you're on a call your cheek will cover the sensor and switch off the screen so that you don't dial anything with your face, but when you move the phone from your ear it's not registering this.
You might need to get your phone looked at as the sensor could be faulty
You can get all the info on repairs here