Hi, little update, the pch was shorted. I asked a friend of mine who works in an electronic school to change it with the bga repair station. He successfully changed it but detected 1 short in the X-Ray machine. I told him to give up because that was a pain since the beginning.
Thank you every one for your help !
Announcement
Collapse
No announcement yet.
User Profile
Collapse
-
-
Re: Alienware 17 R2 (P43F001) no display
I don't know how to verify the state of the bios and EC, i just reflashed the Bios, but i don't have a EC programmer :/
Leave a comment:
-
Re: Alienware 17 R2 (P43F001) no display
I started to search around the mosfets of the cpu but i don't know how to interpret these values, the mosfets are double mosfets, i don't really know how these works but i got some values :
PQ505 & 506
G1 to GND : 3k to 5k
D1 to GND : 460 ohms
S1 to GND : 17 ohms
G2 to GND : 30k
D2 to GND : 17 ohms
S2 to GND : 0 ohm
PQ503 & 504
G1 to GND : 315 ohms
D1 to GND : 460 ohms
S1 to GND : 17 ohms
G2 to GND : 30k
D2 to GND : 17 ohms...
Leave a comment:
-
Re: Asus UX305CA no screen
Nothing on the thermal camera and 6 amps 1v...
So i guess the reflow was not a success, the 1.2V and Gnd line are really close so that explain the short circuit
Leave a comment:
-
Re: Asus UX305CA no screen
Update : I tried to reflow the ram chips, now i have a short between the 1.2V line and gnd... maybe the reflow wasn't a success (or even did the short) or even one of the ram chips was dead ? or the cpu
I will try a voltage injection tomorow with a thermal camera to see anything
Leave a comment:
-
Re: ACER AN515-51G no display
An other update, i just have to wait a little to get a screen !
So this is a successful fix, it was only the oscillator YC2 !
Thank you everyone for your help, i love this community and i'm learning every day something new !
Leave a comment:
-
Re: ACER AN515-51G no display
I changed the quartz and i have now 1v on the +vcccore every time
But i still can't get a screen yet but it's getting there !
What is the next step ?
Leave a comment:
-
Re: ACER AN515-51G no display
Update 2 : ok this one is tricky ! I followed this guide about the first reset signal [url]https://www.badcaps.net/forum/showthread.php?t=44779[/url]
i test the frequency of the oscillator to see if i have 32.768khz, i have it on the oscillo, i start the board while mesuring on the oscillator and the the +vcccore is present !!
And it works everytime with the oscilloscope, i guess the oscilloscope adds a paralel resistance to the quartz and so enough current can flow through thanks to the paralel resistance of the oscilloscope ! ...
Leave a comment:
-
Re: ACER AN515-51G no display
Update : upon testing i have sometimes the +vcccore that works... it's random i don't know why it shows itself
Leave a comment:
-
Re: ACER AN515-51G no display
I have 3.29V on SYS_PWROK !
Little update but now the amber led for charging does not turn on anymore... this signal come from te SIO
Unfortunately i don't have one, what signal can i look on an oscilloscope to be sure that's it's the SIO that is in need of programming ?
I have an other problem, i can't take measure to the chip PU301, this is a bq chip for the battery (BQ24735RGRR), the moment my multimeter probe touches a pin, the laptop turns off, is this a normal behaviour...Last edited by Garibean; 09-13-2023, 03:12 AM.
Leave a comment:
-
Re: ACER AN515-51G no display
I removed it and replaced it with an other one, nothing changed... i'm clueless on this one :/
it maybe was useless to measure this mosfet because the drain part of the mosfet is connected to cpu and there is a low resistance to the cpu anyway :/
i don't know what to do, i'm a beginner with laptop repair so i learn everyday, but sometimes i'm stuck like this and it's frustrating i just want to toss to the bin the whole board ^^'
(little edit i have 3 ohm and the cpu and not 10 of ohm)...Last edited by Garibean; 09-12-2023, 10:30 AM.
Leave a comment:
-
Re: ACER AN515-51G no display
Little update, i checked the PQ903 MOSFET, it's a AON6314, i measured 16ohm between drain and source, could it be the problem ? it looks like a low side mosfet
Leave a comment:
-
Re: ACER AN515-51G no display
ec_vccst_pg = 1.0v
vr_on = 3.29v
PL907 VCCSA = 38 ohm
PL904 vcccore = 14 ohm
PL906 vccgt = 12 ohm
I forgot to say, sometimes, the board does not start. The board turns on for 5 sec then turn off. I do not know what to think about that...Last edited by Garibean; 09-12-2023, 03:27 AM.
Leave a comment:
-
Re: Asus UX305CA no screen
I don't know how to disable the onboard ram on this model, and i don't think the laptop will work at all given that there is no way to add a stick of ram if i disable the onboard ram
Leave a comment:
-
Re: ACER AN515-51G no display
Nothing seems to stand out, maybe the 11V and 10.5V from UQ1 but i don't know what is it
+2.5v : 2.5v
+1.8vs : 1.8v
+1.2p : 1.22v
uc5
1 : 1v
2 : 1v
6 : 1.8v
7 : 1.8v
8 : 1.8v
9 : 1.8v
13 : 1v
14 : 1v
uc6
6 : 1v
uq1
1 : 5.2v
2 : 5.2v
3 : 3.3v
4 : 5.2v
5 : 3.28v
6 : 3.31v
7 : 3.3v
8 : 3.3v
9 : 3.3v
10 : 10.5v
11 : Gnd
12 : 11.06v
13 : 5.2v
14 : 5.2v...
Leave a comment:
-
ACER AN515-51G no display
Hi
Here i am again, stucked during my repair journey, again with a laptop that does turn on but shows no display.
ACER A515-51G motherboard LA-E892P REV 1C
I tried 3 different BIOS just to be sure but nothing...
I disabled On board RAM (of course i have an other stick of ram inserted), did the UMA procedure to exclude the DGPU
Here what i have so far :
+5VALWP : 5.20V
+3VALWP : 3.3V
+3VS : 3.3V
[B]DRAMRST : 0V[/B]
[B]+VCC_CORE : 0V[/B]
AC_PRESENT : 3.3V
VGACORE : 0.9V
VGACORE_EN...Last edited by Garibean; 08-05-2023, 07:49 AM.
-
Re: Asus UX305CA no screen
I tried a bios with a clean ME but nothing more...
The ram are soldered to the board so i can only look the 2 little ram chips and that's all :/
Any other ideas ?
I forgot to say, when i reset the bios and then i turn on the laptop, the laptop try to start then turn off then restart and then i have the green led blinking twice
Leave a comment:
-
Re: Asus UX305CA no screen
Yes, i just learned about charge pump with schotky diodes thanks to you ! I didn't know that this circuit existed !
On DRAM_RESET# or (TP_DDR3_DRAMRST_N), i have 0 V when turning on the laptop and 7.34 MOhm to GND. I guess that's not a good sign, this signal come from the cpu... or maybe this is normal ?...
Leave a comment:
-
Re: Asus UX305CA no screen
That's not a mistake, i have 14V on the +12V, i don't really know what i can do with that :/ i just saw that this voltage is used for a mosfet gate for a 3V line, is that a problem ?Last edited by Garibean; 08-02-2023, 01:00 PM.
Leave a comment:
No activity results to display
Show More
Leave a comment: