Clevo n870hc / No boot

[Techtiger]

Re: Clevo n870hc / No boot

PU16 test pin 1 17 22 21 20 19 voltage , check the PAD again on continuity mode, check PC237 PC86 any short & PQ42 PQ43 S D G for short

[cdgold3]

Re: Clevo n870hc / No boot

Right, Found a 5v feed on Q49 pin 2/3 and on r699

[cdgold3]

Re: Clevo n870hc / No boot

PU16 test pin 1 17 22 21 20 19 voltage , check the PAD again on continuity mode, check PC237 PC86 any short & PQ42 PQ43 S D G for short

Was working around PU16 before you posted

as VVD3 is working with 3.3v and measuring the pins i get:

pin 10 - UGATE2 4.47v (Guessing trigger votage?)
pin 12 - LGATE2 0.03v (Guessing trigger votage?)

VVD5

pin 21 - UGATE1 0.00v
pin 19 - LGATE1 0.00v

[cdgold3]

Re: Clevo n870hc / No boot

pu16 test pin 1 17 22 21 20 19 voltage , check the pad again on continuity mode, check pc237 pc86 any short & pq42 pq43 s d g for short

1 - 0.00
17 0.08- 0.09
19 0.00
20 0.00
21 0.00
22 4.49

[Techtiger]

Re: Clevo n870hc / No boot

Make sure PR345 62K ,PC235 is Good ,PQ42/43 S D G you must test, remove PC 237 to see if you get 5V but don’t trigger

[cdgold3]

Re: Clevo n870hc / No boot

Make sure PR345 62K ,PC235 is Good ,PQ42/43 S D G you must test, remove PC 237 to see if you get 5V but don’t trigger

Hi tachtiger,

Really appreciate your help

Last night i found that there was no VREG5 on pin1 on PU16.

I tracked from Q49 Pin 2 to R700 and got 4.47v. Unfortunately i may have caused a shorted something when looking at PC235. So now i have a short to ground on the 19v rail.

Before the above i removed PQ43 and PQ42 and they seemed ok. just they are not getting a signal to trigger.

I tried removing both U16 and PC235 and still got the short. So at the moment i am now tracking the 19v short but i think its coming from the right bottom of the board. If i ground and touch pc225, pc223, pc211 and pc222 i get ground on both sides.

I have removed pc225, pc223 and still get the short but i am still looking.

Testing say pc242 and C763 there is ground only to one side so the issue maybe in just that area.

I followed this blog in testing the PU16 just to see what was going on

https://www.leakymosfet.com/blogs/ne...aulty-tps51125

[cdgold3]

Re: Clevo n870hc / No boot

PQ39 was faulty, now have 19v again

[cdgold3]

Re: Clevo n870hc / No boot

PQ39 was faulty, now have 19v again

after replacing PQ39 that fixed the short to AC but i found another on PC221,PC222

After removing PJ44 short disappeared from side 1 but side 2 is still to ground.

I cant work out where side 2 connects to. Can anyone point me in the right direction?