Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

[mcplslg123]

Modelell Inspiron 5520
MB:LA-8241P(Discrete)

Problem Description:

It works perfectly fine with adapter.
Battery charging is fine.
Doesnt give display with battery only(It triggers from battery alone but nothing on screen as it doesnt post.
Works fine with Adapter+battery connected but the moment you remove adapter, there is garbage like display on screen for few seconds and then it shuts off.

Voltage on all coils are present on battery also and they are exactly identical when working with adapter. So no voltage drop on coils.
Battery is 100% ok and its not graphics issue.

I've solved the case but will like you to scratch your head a bit on how to solve this problem.

COMMENTS/IDEAS SHOULD BE GIVEN BY FRESHERS ONLY as experienced members can solve it own their own in few minutes.

PS: Will share the solution if and only if you make an honest attempt to solve it.

[koby058]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

is it related to back light ?

[koby058]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

related to secondary display adapter/ driver?

[BalkanBoy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

When you unplug it you said it shuts off after 2-3 seconds or it stays ON but screen goes out?

Everything you said doesn't make any sense, can you give some more hints? Does it switch to integrated once you unplug it? Some bad cap perhaps?

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

When you unplug it you said it shuts off after 2-3 seconds or it stays ON but screen goes out?

Everything you said doesn't make any sense, can you give some more hints? Does it switch to integrated once you unplug it? Some bad cap perhaps?

It switchs off completely after 3-5 seconds. It doesnt switch to integrated graphics. No bad caps in this story. Sorry cant give more hints.

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

related to secondary display adapter/ driver?

Nope

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

is it related to back light ?

Nope. It shuts down completely after 3-5 seconds when you unplug adapter.

[usyusy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

sir, when you power on it after its powered-off, does it instantly power on or take some time

[usyusy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Battery discharging mosfet faulty?

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

sir, when you power on it after its powered-off, does it instantly power on or take some time

Instant powers on

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Battery discharging mosfet faulty?

No. Everthing is good in charging/discharging circuit.

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

I started this thread to improve the problem solving skills of newbie's but lack of response hurts me. You people dont want to learn even when its free??

[BalkanBoy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Battery discharging mosfet faulty?

I guess that would result in instant power off, this is something weird. I had issue where you couldn't power on laptop unless you plug it in 1st, and you can unplug it after that, it was some bloody diode faulty, but this is realy realy strange.

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Thats why i've put it here to improve badcaps community knowledge. I'm always for knowledge sharing.

[usyusy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Thats why i've put it here to improve badcaps community knowledge. I'm always for knowledge sharing.

definitely strange and knowledge enhancing, the issue seems to be a strategic one.

some sensing line issue of any ic?

[usyusy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

sir please disclose the secret.

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Sorry, I wont disclose the solution as the response was very poor and that perhaps a reflects that most of the new members are here to seek help but dont want to learn.

I request admin to close the thread.

[usyusy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Sorry, I wont disclose the solution as the response was very poor and that perhaps a reflects that most of the new members are here to seek help but dont want to learn.

I request admin to close the thread.

You are right sir, learning is the main point and, should, as well as, must be, no one will be there ever to help but learning!
(As till today we remember our teachers' styles, tips-cum-talkings but they have disappeared in the dust of time)

[BalkanBoy]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Ok, one more thing. Is this something that we could apply to any other laptop or better thing to say, is it something that we can solve logically or it's something that we must open schematics and start digging?

I fix laptops for a hobby and I'm definitely not a pro, but still I fixed lot of various faults and this one is really strange, I have never met it. You said there's no voltage drop on any coil when it's on battery but it artefacts when you unplug it and no POST when powering ON on battery. How's that possible? It's got to do something with video card or video ram, maybe DDR3 as well if it boots over integrated which I believe it does.

[mcplslg123]

Re: Dell Inspiron 5520 LA-8241P Not working with battery(For freshers only)

Yes this isbit typical fault which you dont come across on daily basis. I repeat again, there is nothing wrong with discrete graphics chip. Yes there is no voltage drop on any coils between ac/battery.

You can identify the fault even without schematics as i've done. I only opened diagram to look into details of faulty component.

My only intention was to share experience and improve community's knowledge. I've seen many people running paid groups and putting these type of typical cases there to make some money but i'm not for it. Unfortunately, badcaps community has proven me wrong-members are interested only in tips/solution but dont want to learn. these same people are willing to pay for so called paid groups. Ironical but true.