I have here working with Lenovo g570 UMA version LA-675AP rev:1.0 , the problem is laptop turns on then a seconds it goes off, I already tried both flash main and ec bios but still same issue, I noticed the all tantalum 330uf and ceramic around cpu area are both shorted, tried replacing one of them PC711 still shorted, tried replace ISL 95831 PU601 still shorted, also tried removing each component and cpu but all caps are shorted, also PQ601 and PQ602 both drain connected to PC711 are all shorted, anyone can help on this please
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Re: Lenovo G570 shorted vcore
Vcore is often a low voltage power rail. Respectively, it is common to show low resistance on that rail. This does not imply a shorted component is on that rail.
Post the resistance to ground on that rail.
Post the schematic & boardview files for this logic board. -
Re: Lenovo G570 shorted vcore
resistance on PC711 positive side 33.5ohms same with mosfet pq703 drain sideComment
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Re: Lenovo G570 shorted vcore
1) 33.5 ohms does not sound like a shorted part on this rail.
2) Remove the battery & adapter. What is the resistance to ground on PL301, pin # 2 ? Checking for a low resistance on this rail due to a short.
3) Do the same measurement for other coils on the logic board.Comment
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Re: Lenovo G570 shorted vcore
PL301 measures starts from 12mohms dropping 200k then rising up, Pr326 has 5.1ohms, the mosfet pq310 and pq313 resistance is fluctuating,Comment
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Re: Lenovo G570 shorted vcore
Measure resistance on all coils and report back. Is the resistance fluctuating by a lot? Measure continuity in diode mode across PQ310 and PQ313.Comment
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Hi, Would appreciate some help.
I have an Apple Late 2013 15" A1398 MacBook Pro with Logic Board 820-3662.
Get charger light but no fan spin or chime. No liquid damage.
Found PPBUS and VCORE both shorted to ground. Other rails were ok.
Removed VCORE MOSFETS U7310, U7320 and U7330. Found U7330 was in fact shorted.
With the 3 MOSFETS removed, get PPBUS and fan spin. VCORE is still hard shorted to ground (0 ohms).
Attempted voltage insertion on VCORE to locate short using bench supply set at 1.0 VDC and 4.95 Amps (max current for my... -
Hello,
I have water damaged Dell G3 3779.
Things I did. During visual inspection i noticed PL911 filter was blown up and caps around it PC901, PC902 .. all up to PU901 shorted, found culprit shorted cap on top side of board PC905, removed cap and short up to PU901 is gone. Shorted PJP901 to bypass filter for the moment.
problem is CPU and GPU vcore coils are all shorted aswell and I don't know where can I safely inject power to test which component or driver is bad.
PLA01 20.8 Ohm PLI01 3.8 Ohm, PLI02 3.8 Ohm, PLI03 3.8 Ohm, PLI04 3.8 Ohm... -
Model: Lenovo Slim 7 14IAP7
Motherboard: NM-E412
Please, take a look at the enclosed photo and help me identify this IC. It is currently shorted, no boardview or schematics, I am unable to make out what this is.
The chip has markings "Y182" on line 1 and "2898" on line 2.
Thank you.... -
Hi, i have a Lenovo S145 that after 20 seconds shutdown and restart (it's working correctly on thse 20 seconds)
everything seems ok, but on Vcore inductor ( this is an i3 with just 1 switching power supply for CPU)
there is an output to teh CPU with a spike.. seems that inductor can't handle the input...
replaced the capacitor (330) and the inductor (R15) without any change
any idea? very thank you!
input of the inductor seems as usual... only strange thing is that the upper/lower voltages seems to be 21V (main power line is 19.3) ... but not sure this... -
Lenovo G470 G570 LA-6759P Boardview
Rev 1.0...10-22-2024, 03:48 AM
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