still have no backlight. External display works fine
I am having the same issue... however I replaced my entire display before bothering to check the backlight fuse. After replacing the display, I looked into the backlight fuse and it tested fine but I still have no backlight. External display works fine. No short in the display circuitry either. Kind of lost from here.
Update (12/21/2016)
@oldturkey03 Also, I was looking at it with my phone earlier and noticed that there are some potentially bad pins on the LVDS connector. Could this be causing the backlight issue? When I look at the schematics, the suspicious pins don't seem to be related to backlight..
http://i.imgur.com/O9TbOUi.jpg
Pins 10,11,12 seem fried..
Questa è una buona domanda?
2 Commenti
@jbwftw what model is your logicboard 820-XXXX and besides buying a new display what have you checked? How did you check for "no short in the display circuitry"?
da oldturkey03
@oldturkey03
I have the 820-2936-B
I tested for the short by using a multimeter, with the ground on the exit of the circuit on C9799 and a positive on the ground. Found out that trick from a MBP repair shop's youtube channel.
I also used my multimeter to test the fuse for continuity... it showed the fuse was good, but I have a junky harbor freight mm so I am ordering a new one to retest.
As I replaced the entire display assembly, this means that I have also used new cables and everything else that comes attached to the assembly.
Can the U9701 chip go bad entirely and still allow me to get external video, or is it only responsible for the backlight? I should also note that this motherboard used to not work after a coffee spill, so I was able to get it working again with some alcohol
da Jacob Williams