Chosen Solution
Hello. I wish to find out which two from the four pins from the LED backlight actually use 16v. Which is plus and which is minus? I have a backlight issue that it’s to expensive to repair around here and need a cheaper solution. Unorthodox maybe, but this doesn’t involve motherboard soldering. Update (02/08/2018) Thanks. I figured it out. Since they are LEDs… They don’t get burned when the polarity is wrong. So I found out that the first and the third contacts, starting from upper side, were those I wanted. Again, I didn’t pay attention to polarity. It worked. If it didn’t, then I just needed to solder the wires the other way. I have tested with a 16v transformer from a printer and from an iPhone 4 and 6. iPhone 4 would only power up half of the LEDs. But you MUST have it already connected, or else it will only send juice for a fraction of a second. Tested on my tongue and with a power meter. It’s good that it’s only a jolt, so it won’t blow up it’s filter or whatever it has before the LCD connector. Was fun. Now I have 2 apples on a branch lmao.
I am not really certain what exactly you are asking; will you be trying to directly power the backlight? The backlight circuit is one anode (driving the ~16V) and two cathodes (return paths). That is what the circuit on the logic board looks like. If you are trying to connect directly to the soldered flex connector on the display, they tend to vary from one supplier to the next. One trick is to use a 9V battery or a DCPS and power the backlight directly to see what is what. If this doesn’t answer your question, get back to me with more details and/or pictures.
