Dead Lenovo Thinkpad Edge E520 (BIOS ?)

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Anybody can help with this issue?
I'm a beginner, but I have measuring instrument(I have a scope too) and I can follow instructions. I repair TVs, home theater receivers and other devices as a hobby.
I have replaced the BD9528, but there is no change.
Ref is 2V though
I'm in pretty much same situation as the op.
At pin #14, at U2701 I have a constant 3.2V, no matter the state of the power on switch.
First of all, what I need to have plugged into the mainboard? CPU, memory, BIOS battery and power switch? I don't have connected the little daughter board with the card adapter and a USB port, DVD drive, any of the touchpad, keyboard, speakers, LEDs, screen, HDD.
Any help would be appreciated.

Tibor

[c_hegge]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

This is a known defect on these. I -think- it may be the BIOS chip that needs replacing, but I don't know for sure. There may be other parts that get damaged by the failure of the chip in question.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

I know about the EEPROM issue, but from where can I get one?
There are some basic measurements, that I can do, to see if everything is good hardware wise?
I know a TV, always has a standby voltage, when it's plugged in. When the remote, or power button is depressed, the main board sends the command to the power supply, to turn on and also sends the signal to the backlight, to also turn on.
On what principle, is working a laptop?

[khaahk]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

It somewhat differs from one manufacturer to other, but mainly the EC (U2701) needs to have 3.3V, it reads part of the bios(U6001) to get its program code and sets itself to working order. Then it waits for power button to be pressed.
You have EC powered, does the powerbutton press translate to low level on pin 93 on U2701? If it is, then next i think that PM_PWRBTN# should be sent to PCH. If not, then either bios is bad or EC is not working. There are of course control signal (LID an AC status etc) which should be in correct states also.
You do not need to change the bios, only reprogram it on most occasions. So you need to get programmer.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Thanks for trying to help.
First of all, can I ask what has to be hooked up to the mobo?
There is a express card/USB daughter card, which I have not hooked it up to the board, none of the touch pad/keyboard/LED, LCD, DVD.
I have the mobo, one memory stick, BIOS battery and CPU.
Battery, has to be hooked up?
In this state, I'm getting at pin #93= 0.013V and when I push the power on button, it goes to 0V.
What is EC?
What I'm hearing is, that the EEPROM itself gets bad and needs replacing.
I'm about to get a programmer(not just for this application), but I'm not sure which one to get.
I need it for nand flashes also.
I have noticed that the MCUMALL GQ-5X has a nand flash version coming soon and also a SPI version.
I have never done anything like this and I don't know which device to get to start learning the programming.
I need it for programming TV, laptop, monitor EEPROMS and a nand flash in Kenwood double dins(Toshiba TC58NVGxxxxx).
On Ebay, they sell EEPROMS for this laptop, but it's $25. I would rather get a programmer and the chip and I would like to do it myself.
I need all the help, that I can get. I'm way over my head here.
I appreciate any help that I can get.

[khaahk]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

You need CPU, memory connected. USB daughtercards are not needed.
EC = embedded controller, multicontroller, eg. microcontroller which controls the laptop power states, various inputs/outputs, the keyboard and PS2 mouse.
You have 0V on power button, but EC has power? (pins 19,46, etc) meaning EC is not working correctly. Either it does not have correct program to work on (meaning bad BIOS), or it is defective.

Take measurements:
1. Voltage on pin 19 of EC (3.3V)
2. Voltage on pin 93 (according to your info 0.1V), is it correct?
3. Voltage on pin 8 of U6001 (Bios VCC, 3.3V)
4. If 3. present, then check pin 2,6 of U6001 for data traffic (square impulses of ~3V)
first moments when power connected to mainboard, use your oscilloscope

About purchasing a programmer, it has been discussed here before i think. Q5X has the NAND version separate of the spi version. Get a separate spi programmer.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

There is (constant)3V at the button.

[khaahk]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

That 3V should be also on pin 93 of EC. Search for R2703, is it correct value?
Resistance from pin 93 of EC to gnd? What about bios power and impulses?

[Alfa is auto]

here

http://www.ebay.com/sch/i.html?_from...Text=&_sacat=0

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

I know about that, but I rather buy a programmer(with this, I'm learning also) and after a couple EEPROMs, it pays for itself.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Today, I'm measuring again the button and pin #93, pin #14 and I'm not getting anything.That is weird.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Anybody has a service manual for this model E520? I'm still using the E420 and I'm not sure if it's the same.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

I have replaced the BIOS chip and nothing happened(Ebay-biosdepot).
Any help would be appreciated.
I really need some help here.

Tibor

[fddizon]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

post a clear picture top and bottom of the mobo

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Here is to late, but tomorrow I will do that.
I think, that I don't have 3.3V.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Here are the pictures.

[khaahk]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Right upper side of the 1st pic is what, near the m-pcie connector?

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

There are some parts under the tape. I did not look there yet.

[tibimakai]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

Any ideas, where should I start?

[fddizon]

Re: Dead Lenovo Thinkpad Edge E520 (BIOS ?)

check the output of those voltages, usually on coils. post schematic.