acer aspire 5920g no post after shorted mxm connector plus battery led on without bat

[dellxps15]

hi, i have a acer aspire 5920g that was previously shorted by removing mxm card with battery connected. after replace the kb that was getting very hot, not pc fan spin, but i have battery charge led indicator turning on even if battery is not present, and notebook didnt post. pc fan start spin and do this:

withouit mxm card monitor backlight turns on but no post or video also on external monitor

with mxm monitor backlight doesnt turn on.


my 2 major problem are this battery charge indicator and no display. i have checked all coils and voltage are present.

reprogrammed also bios with same result.

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

ok, tried a know working vga and as suspected pc is working fine except that battery charge indicator that turns on even without battery...

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

some testing thought me that in orange led i have pr14 5v one side 5v the other and pr15 5volt one side and 0volt the other side, while in normal mainboard i have pr14 5v one side 0 the other and pr15 5volt both side.

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

tested and compared 2 board. on the normal board, i have 12volt going to battery and going back to 0 when battery is not present.
on the non working board, i have 12volt going to battery and stay there more till red light turns on.

in both board isl6251 enable is 5 volt. so it's always enablet to charge battery, but for some reson on the normal board it detect battery if present or not, in the other not.

any advice would be good.

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

today i changed pq29, isl6251 but still the same. laptop want to charge a non present battery....

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

no one ?

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

here is isl6251 voltage pin:

1) 5v
2) 1.38v
3) 4.98v
4) 0
5) 1.8v
6) 0.74v
7) 0
8) 2.37v
9) 0v
10) 1.42v
11) 0.92v
12) 0v
13) 0
14) 0v
15) 5v
16) 14.89v
17) 12.12v
18) 11.48v
19) 19.33v
20) 19.33v
21) 12.51v
22) 12.51v
23) 0v
24) 19.2v

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

noone can help me figuring out whats wrong with this battery charger?


could it be a bulk wpc8769 chip ?

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

i noteiced today that if i touch pr11 zone with finger it stop recharging... passed pr11 pr6 solder but still the same...

what is che pin that detect battery if present and is bad here ?

[bachir2004]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

hello everybody;I am new here and many thanks to everybody on this wonderfull site.For your problem here dellxps I would suspect a bad wpc8769 chip,since this chip controls the mxm pwrok and the leds of charging.those chips have always made me mad.Hope it can help and good luck.

[dellxps15]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

hi, for the mxm now pc works fine. for the led it's true they are controlled by the winbond, but when i have orange led, i see 12.5 volt on battery connector even if battery is not present.... and that part is making me mad about that. tried also changing isl6251 but no luck. winbond wpc8769 is new. my only question is i bought it bulk... maybe they are not original and works different ? dunno what is telling the fet to be opened as i write there i have the 5 volt enabled on 2 laptops and one recharge and one not even when battery is not connected.

[bachir2004]

Re: acer aspire 5920g no post after shorted mxm connector plus battery led on without

Only thing that seems logical is to change the WPC.I have used these new chips only twice,cannot tell you.However,I prefer to use those from used motherboards after some random checks.Good luck.