acer d260 netbook nav50 la-5651p

[dellxps15]

hi again, i have this netbook with chemical substance spilled over it.
after clean the board, i have tryed to boot but with no success. power come on but no screen, so tried with external lcd but same story. after some try, pc wont start annymore and i have spotted 2 burned resistor as shown in the picture.
probably that burn was caused by the damaged 3 pin fan connector cracked by that chemical substance and got fragile that make the 3 pin go arount till they have touched something while i was trying vga monitor.

that is what i think has happened.

i have now replaced them both. all coil are ok ( no short). if i look for 3 and 5 volt always they are present. if i press power button and check for kb controller pin 32, it pass from 2.9 volt to 0.5 volt when i press the power botton, so switch sould work. i have tried almost all, cant find why it wont start. also on the kb controller i see pin 32 is power button in and dont see any power S3 or S1 state output... (page 17)

if i press power botton, no other voltage from coil except 3 and 5 volt always.

any suggestion would be appreciated

[tomodachi]

Re: acer d260 netbook nav50 la-5651p

is there any voltage at power button pins ? like 3.3 or 19V ? if it present then I guess chemical spill on fan connector may be caused KBC fault or a bad eprom, or BIOS. Also check the board for any overheating components, there might be a broken IC which you can not detect with multimeter.

[spleenharvester]

Re: acer d260 netbook nav50 la-5651p

Given those resistors are on the VIN circuit, and 3VALW and 5VALW are present, I would hazard a guess that they are not causing the fault you are experiencing.

I would take a look at the FAN1 connector schematic on page 4 and test in that area. Might be worth checking if THERMTRIP# is pulled low or not.

From what I can gather, it boots but no POST? Or did it stop booting after replacing the resistors?

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

Given those resistors are on the VIN circuit, and 3VALW and 5VALW are present, I would hazard a guess that they are not causing the fault you are experiencing.

I would take a look at the FAN1 connector schematic on page 4 and test in that area. Might be worth checking if THERMTRIP# is pulled low or not.

From what I can gather, it boots but no POST? Or did it stop booting after replacing the resistors?

it just stop booting after fan cable short something i guess.....

tomorrow ill check 3.3 volt on the kb controller...

tnx for reply

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

on the power botton i have 2.9 volt (called sw1 in the schematics) so it is ok

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

ok , i have checked 5valwp and 3valwp to 5vs and 3vs and i havent the VSB voltage. so i looked on page 24 of the schematic and i have voltage like in the picture, so is that pr32 the problem?

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

got another look today and on pin 32 of the SIO controller U6 i have 3.2 volt. if i press power botton it drop to 0.5 volt (not 0....) and on pin 95 (SYSON) i have nothing pressing power botton....

any help?

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

did another read and have all voltage ok on pin: 9-22-33-96-111-125-37-118-109

on pin 95 i have 0 volt.

pin 75 is 0 volt. (normal as it is volt that come on when power on is ok)

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

checked bios rom u76 (u75 not present) and have 3.3 volt on pin 3-7-8, have 3.3 volt on pin 1 going to 0.2 volt if press power botton, from 0.2 to 0.5 max oscillating not stable volt on pin 2, 0volt on pin4, 0volt on pin5 going to 0.2volt if i press power botton, 0 -0.2volt on pin 6 going to 1.5volt if press power botton.


i need a board view for that....

[fddizon]

Re: acer d260 netbook nav50 la-5651p

check pin 100 (RSMRST) if 3v to 3.3v will come after pressing power button...

if no output after pressing power button, check sio vin, ecrst, clock signal, and CS to bios chip

[fddizon]

Re: acer d260 netbook nav50 la-5651p

try to reprogram BIOS if pin 1 of u76 is not stable

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

pin1 of u76 has stable 3.3 volt. it go to 0volt if i press power botton.

pin 100 has 0 volt. if i press power botton it goes to 3.3 volt.

tnx for help

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

today i flashed bios and put it back, but probably some solder wasnt ok because no volt on pin 1-3-8, so did a reflow and while measuring voltage coming it power on.... turned it off, then no more power. dira check on the solder and all seems ok, but no more power on.

i have 3.6volt on pin 1-3-7-8. on pin 2 and 6 from 0 it go to 1.6 when pressing power botton

pin 4 is always 0 and pin 5 go from 0 to 0.2 volt.

this netbook has 2 power led indicator, one in front and one down the power botton switch.

if i press power botton, front one light up for 2-3 seconds, while the read did nothing.

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

ok, i have discovered that main 3valws and 5valws ic pu4 get hot. after touching it a bit with finger it make some noise and pc started.....

is that pu4 the problem or maybe some bad capacitor ?

[whaldsz]

Re: acer d260 netbook nav50 la-5651p

ok, i have discovered that main 3valws and 5valws ic pu4 get hot. after touching it a bit with finger it make some noise and pc started.....

is that pu4 the problem or maybe some bad capacitor ?

It means there's a short somewhere, to isolate where the short is coming from . Do the following and post back your results:

1. Disconnect PJ1 and check if PU4 is still getting hot. If it is, the short is in the +3VALW.
2. Disconnect PJ2 and check if PU4 is still getting hot. If it is getting hot, the short is in the +5VALW.

You can continue desoldering the jumpers on page 23 of the schematic to pinpoint the location of the shorted components. You might need to test the MOSFET though.

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

changed pu4 and now pc light comes on . also all voltage on coils are present, but i have no video. maybe because i dont have any fans connected ?

edit: connected fan still the same..... atom reflow ?

edit2: on pin 2-3 of q3 i have 3 volt. 0volt on pin 1.

on q4 i have volt on pin2
on q5 i have volt on pin 1

on L1 i have 19volt

bad q3 ?

NTR4101PT1G 1P SOT-23-3 is Q3 where can i find it in europe ?

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

can someone explain me that circuit ?

is it a gmc problem ?

r174 is 66k instead of 100.... change it ?

edit changed and also 66k.

edit2: whaaaaaaaaaaaaaaaaaaaaa changed another ram (used a 512mb and tryed with a 1gb ) and.... it works


tryed other ram before changing pu4, but not this time

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

hi, today i got another nav50 acer 260d mainboard. it works fine with battery, but dont boot on power supply only. with psu i have no 3.3 and 5 volt. on pr57 i have about 1.5 volt.
on pq10 i have 18volt on pin 1-2-3. i have 16volt on pin 4 and 1.5 volt on pin 5-6-7-8.

so i suspect pin 4 should be lower to enable that fet.

can someone explain please that circui part on page 25 ?

tnx in advance

[khaahk]

Re: acer d260 netbook nav50 la-5651p

pq20 gate voltage?

[dellxps15]

Re: acer d260 netbook nav50 la-5651p

i have a working and no working board. the first difference i see are on pq12 pin 3 ; in working board i have 7.5volt, while in the non working i have 15.79v.