820-00840-A FaceTime error "no video"

[mbcontrol]

I fixed this board (liquid damage). At the final test FaceTime shows this error message (translation from german):
"No Video - FaceTime couldn't get a videosignal from the connected camera. Maybe a restart can fix the problem."

The ALS is working. Same behavior with two displays. The camera LED is blinking.

I've never had this bug before. Do you have any idea where to start troubleshooting.

 

[tcampbell34]

I had a similar issue on the same model board and it was a blown L4085 that caused it. Check that and the other components in that area to make sure they are good.

 

[2informaticos]

Is the camera recognized into system report?
Check all the signal coils from page 37, listed under Camera Sensor area.
Apart of L4010, which is good; because ALS is working.

 

[mbcontrol]

The issue is fixed - i changed L4084 and L4085. Thanks for giving me the right tip.

Just for information:
Yes, the system did show the camera.
The coils was visually looking good, also the caps.
Before changing the coils i had a look with the oszilloscope (see screenshots).
MIPI_DATA_F_N (L4084) there was no data signal.
MIPI_DATA_F_P (L4085) there was no clean low signal (see the top row with the 4 screenshots)