dell inspiron N7110 LCD no back light

[bigsam731]

Hello all. I'm new to the community and my apologies if this was discussed in a previous post. I have a Inspiron 17R N7110 that has dim backlight to the LCD. When I plug it it to an external monitor i can see everything in that monitor. I searched every where for a solution but nothing on my model, all I find is solutions for the 1545 model which tells me to replace the F1 or F8 fuse. If that's the case on mine, does anyone know where are those fuses located? thanks in advance

My motherboard model is
DA0R03MB6E0 REV; E

 

[bigsam731]

I did some thing similar today. I took R472 out of circuit and tried to give pin 36 3.3v from external power source. But before I did, I remeasured pin 36 it's still had 19V. I didn't want to give it too much voltage. I also measured pin 18 of IT8518 and of course I had 19V. I think I have a defective IT8518. I'm going to try out you theory tomorrow, since I have another cable anyway, and see if I get some light on that LCD.

 

[bigsam731]

From the specifications of your screen, on pin 36 you should have 3.3 volts for the screen to be enable. I think the chip (IT8518) on page 23 who control this pin is defective. A test you can perform, but this is on your own if something goes wrong, but trust me, you have to open the wire for the pin 36 on the cable from the motherboard, and connect this wire going to pin 36 to the screen to the pin 2 off the connector, in that way you give 3.3 volts to pins 36 for the screen from pin 2.

OK... I did what you said by rewiring pin 36 and attached it pin 2 and and I FINALLY have back light. I Know its a bad soldering job but I figured I"ll give it a try. Here are some pics...

https://drive.google.com/open?id=0B4eDDk7o_vmnYUV6R2JxcmpwUHo3OS1CTWJWUkc0b082cnhB
https://drive.google.com/open?id=0B4eDDk7o_vmnSlNrR3J3SEd6M0RJaEdxZXBWRVZNbHB0S05B

 

[jarotech]

Good job, put some tape on it to isolate and leave it like that, in this way it's better than changing the chip IT8518.

 

[bigsam731]

LOL. As tempted as I'm to change that chip I think I'll just settle for the tape. Who knows, I might get the urge next week and change it.
Thank you for all your help. I really appreciate it.

 

[jarotech]

Until the next problem.