Hello!

I have here laptop Lenovo y510p
Laptop starts, displays no picture, cpu and gpu remain cold, so no current to gpu or cpu.

i have inspected the motherboard, no burnmarks, i have downloaded bios dumps ec+main and reflashed bios, same thing.

i have checked pu501 chip . i have found that there is 19.5v on pr506 , but on other side which is going to pu501 i had 17.7v so i jumped the pr506 with a wire and that burned pu501 :) (i am noob)
i have removed pq501 and pq502 and tested them outside of the motherboard

pq501

S->G = OL
G->S = OL
S->D = from 0.9 up to xxx constantly changing and going up +1 every second
D->S = from 0.330 up to 0.xxx constantly changing and going up +1 every second (when i charge the gate then it is OL )
D->G = OL
G->D = OL

pq502

S->G= OL
G->S = OL
D->G = OL
G->D = OL
S->D = 0,148 (doesnt change when i charge gate stays the same )
D->S = OL (doesnt change when gate is charged)

pq501 bad?

i have purchased new pu501 which is burned and will replace it,

pq501 is SIS472DN-T1-GE3
pq502 is SISA12DN-T1-GE3

if pq501 and pq502 are bad, which equivalents i can use? i have AO4710 , is this ok?
If pq501 and pq502 are good, what else should i check? Maybe EC bad? does EC have his own program or his program is in BIOS (ec dump) ?

thank you

Hey. Yes, EC have its own firmware inside. First you should temporarily remove PU501, PL501 and PL502 (i guess PQ501 and PQ502 is desoldered now, remove them also if no), and then measure resistance to ground on that choke's solder pads. If that pads are not shorted to ground, replace PU501 along with both PQ501 and PQ502, solder back chokes and try. You also may got burnt RAM after shorting that resistor, so keep it in mind.

ok, so i cannot use any ec chip, i must use the same model from the same machine? :(

i will replace all 3 chips pu501 pq501 and pq502

memory is not burned, the pu501 burned out as soon as i plugged in the charger
so it is pu501 or ec chip fail?

can another ec chip be programmed?