Hi @all,
I´m stuck in the repair process for a Lenovo P52, Model: 20M9001MGE.
What was the problem:
The problem was a boot loop, it started all over again and again.
Unfortunately the internal display is missing, so I plugged a external monitor, but there was no output.
I´ve then dissasembled everything and flashed the bios chip with a clean bios. https://www.badcaps.net/forum/showth...&highlight=P52.
What´s the problem now
The charging light lights up, when I connect the power cable and have the battery pluged in.
The power button-LED lights 3 times, when I connect the power cable.
But when I press the power button, nothing happens.
When I´ve only insert the battery, there is just a very weak light on the power button-LED for a second, when I press it. There is no fan spinning or other signs of life.
What I´ve tried already
Reseated the RAM and try with a known good one. Power drain everything multiple times.
Flashed a few other BIOS-Versions I´ve found.
I think it´s not a BIOS problem anymore, there must be something wrong with the hardware.
I need help to get a starting point where I should look. I´ve already watched a ton of videos, and checked a few things with the multimeter, but no problem described in the videos applies to this board.
Update 1: Checked the voltage after the DC-Input, 20 Volts are present at the Power fuse 1 and at the current resistor, marked "R005".
Update 2: Checked the 3,3 rail, and think it´s okay, but I´m not sure, can anybody please check with the schematics (see attachement)?
Readings:
PJ11 = 0V
PJ12 = 5,19V
PJ15 = 1,85V
PJ16 = 0V
PJ17 = 0V
PJ18 = 0V
PJ19 = 20,6V
PJ20 = 5,2V
Could someone give me a little help and point me in the right direction?
thanks in advance
https://www.badcaps.net/forum/showthread.php?t=106150
I´m stuck in the repair process for a Lenovo P52, Model: 20M9001MGE.
What was the problem:
The problem was a boot loop, it started all over again and again.
Unfortunately the internal display is missing, so I plugged a external monitor, but there was no output.
I´ve then dissasembled everything and flashed the bios chip with a clean bios. https://www.badcaps.net/forum/showth...&highlight=P52.
What´s the problem now
The charging light lights up, when I connect the power cable and have the battery pluged in.
The power button-LED lights 3 times, when I connect the power cable.
But when I press the power button, nothing happens.
When I´ve only insert the battery, there is just a very weak light on the power button-LED for a second, when I press it. There is no fan spinning or other signs of life.
What I´ve tried already
Reseated the RAM and try with a known good one. Power drain everything multiple times.
Flashed a few other BIOS-Versions I´ve found.
I think it´s not a BIOS problem anymore, there must be something wrong with the hardware.
I need help to get a starting point where I should look. I´ve already watched a ton of videos, and checked a few things with the multimeter, but no problem described in the videos applies to this board.
Update 1: Checked the voltage after the DC-Input, 20 Volts are present at the Power fuse 1 and at the current resistor, marked "R005".
Update 2: Checked the 3,3 rail, and think it´s okay, but I´m not sure, can anybody please check with the schematics (see attachement)?
Readings:
PJ11 = 0V
PJ12 = 5,19V
PJ15 = 1,85V
PJ16 = 0V
PJ17 = 0V
PJ18 = 0V
PJ19 = 20,6V
PJ20 = 5,2V
Could someone give me a little help and point me in the right direction?
thanks in advance
https://www.badcaps.net/forum/showthread.php?t=106150
Attached Files
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