Problem with camera, sound and backlight

[Zaanoo]

Hello guys,

I come here with a big problem and i am looking for some help. I know it can be resultless, but well let's start. So i have my own business and sometimes my employees make mistakes and buy not 100% working phones which later I repair on myself. Its because in most of cases there is no warranty on them and giving it to the service would be too expensive and not profitable. I've already repaired dozens of Lumia, but this one is the hard one. There are 3 things not working correctly:

1. Camera

Everything works fine until when i try to take a photo. After pressing the button image freezes and nothing can be done than closing camera application. Also it failes in NCS Test with result:

Test name:
Camera interface test

Test description:
Tests that all data lines between camera sensor and CSI receiver are functional

Result:
MINOR

Result (detailed view):
Camera Model ID[2], Major Rev, Minor Rev, Manufacturer ID, Serial Number[10], Sent Frames, Received Packets[2], CRC Status[4], ECC Status[4], NVM checksum[2], NVM calculated checksum[2]
3 187 3 1 10 48 67 49 53 49 55 51 55 48 48 6 0 0 0 0 0 0 0 0 0 0 86 23 86 23

Data description:
Detailed result contains following information:
Camera Model ID (2 bytes, MSB first)
Camera major revision (1 byte)
Camera minor revision (1 byte)
Camera manufacturer ID (1 byte)
Camera serial number (10 ascii characters, if shorter filled with 0x00, by default string is NOT '\\0' terminated)
Number of sent image frames from camera (1 byte)
Number of received packets over CSI-2 data bus (2 bytes, MSB first)
CRC errors detected by the CSI-2 receiver (4 bytes, MSB first)
ECC errors detected by the CSI-2 receiver (4 bytes, MSB first)
Expected NVM checksum (2 bytes, MSB first)
Calculated NVM checksum (2 bytes, MSB first)

Method description:
Test verifies that correct amount of data has been passed from camera sensor to CSI receiver and checks all transfer errors from receiver

2. Sound

Complete lack of sound everywhere, but buzzer works. Funny thing dat somehow after someone called to me sound came back, but when i muted phone it has never back again. Audio controller test passed, but digital microphone not. Im not sure is it somehow related to this problem, but:

Test name:
Digital microphone selftest

Test description:
Test verifies that all microphones on the product are operational.

Result:
MINOR

Result (detailed view):
Failed initializing audio

Data description:
If capturing audio from microphones was possible, first integer array contains the smallest variation found in the channels.
The second integer array contains variations of all active channels separately. These are followed by integer array containing
the smallest cumulative difference between channel pairs, then followed by fourth array containing individual differencies of
channel pairs.

Method description:
One microphone generates 2 channels so that normal microphone part is on one channel and attenuated microphone on another channel.
From captured stream variation is calculated from every channel separately.
In order to make selftest pass the variation has to exceed certain limit on every active channel.
Also cumulative difference between channel pairs (1 & 2, 3 & 4 ...) is calculated. If difference is too small test will fail.

/**
**3. Backlight
**
**There is no backlight in keys, god knows why.
**/
So what I tried: hard reset/soft reset/changing firmwares/checking if all cables are well connected/replacing speaker

Every kind of help will be pleased. I add photos, you can also see yellow blur on screen and little damage on ALS board, but it works fine.

ALBUM: imgur. com/a/R8Upa (remove space, couldnt post link)

Sorry for english mistakes, i hope its readable and understandable.

 

[Nandakumar Kesavan]

Backlight Keys for L1320? i don't think they have it, my L1320 haven't had it from day one, don't think this is an issue.

 

[Zaanoo]

Yeah, my bad. I thought every Lumia has it. At least it makes list shorter :sweaty:

 

[SSgt Bruskowiz]

I believe your mainboard is the problem.
Camera works but as soon it has to write the data to the storage it freezes up. If the camera isn't the issue than is the logical step the mainboard.
The issue with the sound strengths the suspicion.