Lenovo E570 3v Power issue

[coltron]

Hope someone can help with a Lenovo E570 not powering on.

3V Rail missing and ic getting very hot

With reference to link:-

https://www.badcaps.net/forum/showth...highlight=E570

Read later posts for schematics, boardview and latest comments.

SMDFlea comment regarding resistances around the ic, I had already pulled the IC from the board before digesting the suggestion. (because the chip gets very hot with coil getting hot soon after charger is plugged in).

0.2v at the power button, prior to removing the chip.

pin 1 (3v5v on)120kohm
pin 2 (3v p.good) open?
pin 3 (3v alw FB) open?
pin4 (3v alw out ) 902ohm
pin 5 (3vl or n6093) 1ohm
pin 6 (3vbs) open?
pin 7 (3v in) 626ohm
pin 8 ( 3v in ) 626ohm
pin 9 (gnd) 0ohm
pin 10 (3v lx) 902ohm

These are motherboard readings with meter leads black to gnd and red to pin being measured.

The chip itself has no apparent shorts and may be ok?

I'm haven't tried power injection, but my intention is 2v - 2amp onto pin 5.

[mon2]

Re: E570 3v Power issue

If any part is getting hot, remove all power.

Meter in resistance mode.

Check the resistance to ground of the rail linked to the power supply IC that is getting hot.

[coltron]

Re: E570 3v Power issue

Thanks for your comment Mon2.

The resistance value of pin 9 pad on the motherboard is zero ohm, but fair point. How could i check on the grnd pad on the ic?

[coltron]

Re: E570 3v Power issue

On second read of your suggestion

pin 7 and 8 are 3v in, they are both 626 ohm

pin 10 goas to the coil/inductor which has a resistance just under 1k.

[SMDFlea]

Re: E570 3v Power issue

Can you desolder RE3 and check the resistance to ground on both pins

[coltron]

Re: E570 3v Power issue

Ok Thanks SMDflea, I have de - soldered R3 and measured resistances:-

3v-ec = 001
3vl = circa 600


I'm assuming this is bad and points to a short on chip UE1?

[SMDFlea]

Re: E570 3v Power issue

Ok Thanks SMDflea, I have de - soldered R3 and measured resistances:-

3v-ec = 001
3vl = circa 600
I'm assuming this is bad and points to a short on chip UE1?

It could be yes.Inject voltage and see what heats up, start at 1V 1A

[coltron]

Re: E570 3v Power issue

Thanks for reply SMDFlea

Just to be clear, your suggestion is to inject voltage on R3 (ec side)?

(I consider myself very new to this)

[SMDFlea]

Re: E570 3v Power issue

Thanks for reply SMDFlea

Just to be clear, your suggestion is to inject voltage on R3 (ec side)?

(I consider myself very new to this)

Yes on that side. I must be the EC thats shorted

[coltron]

Re: E570 3v Power issue

Thanks and yes, as suspected, the big Lenovo chip gets hot in the middle.

IT8586E
1735 - FXA
ES00KA

I've found one on eBay, :-

IT8586E
1948 - fxa
ECZ3GA

Would this suffice?

[misha97123]

Re: E570 3v Power issue

Thanks and yes, as suspected, the big Lenovo chip gets hot in the middle.

IT8586E
1735 - FXA
ES00KA

I've found one on eBay, :-

IT8586E
1948 - fxa
ECZ3GA

Would this suffice?

yep.
but after soldering a new chip, you need to reflash the 128kb dump for it, is not known kind of garbage inside the chip

[coltron]

Re: E570 3v Power issue

I have a lenovo B50 50 with a similar chip starting with IT8586E, would this chip work with the E570?

[coltron]

Re: E570 3v Power issue

I think its worth mentioning that the laptop this board belongs to had a mangled dc socket, ( sqaure type) the plastic surrounding the centre pin was missing and pins bent.

That,s ebay lol

I believe this may of killed the super i/o chip.

[SMDFlea]

Re: E570 3v Power issue

I have a lenovo B50 50 with a similar chip starting with IT8586E, would this chip work with the E570?

You should use a chip with the same 3 letter suffix FXA. Sometimes you can use one with a different suffix but its trial and error if it will work or not.
Using the EC from the B50 50 might work if it shares the same EC code as the E570 ,it could be generic enough though to make it boot and from there you could update the bios and EC with the update from the support site.If it doesn`t boot then you will have to program the EC,if you have a programmer that will do it,or buy a pre programmed chip from ebay or Ali.
Desolder the old chip and check that the short has truly gone.
.

[coltron]

Re: Lenovo E570 3v Power issue

Sound advice. I will desolder the io chip and go from there. Thanks again

[tomodachi]

Re: Lenovo E570 3v Power issue

could be a codec IC short as well

[coltron]

Re: Lenovo E570 3v Power issue

I,ve comared e570 board view with b50 50 and some of the b50 pins do different things to the e570.

A programmed chip seems the best option though a good value e570 board may appear on Ebay

Thanks everyone for your help.