Testing VRMs

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Asus , board 532lws R1..3 Power rail 5v , 3v dsw

by User 4574

Hi everyone .
I have model g712l And In stuck.
Originally this laptop has a short on main Power rail . Thé main short is gone, i have found 2 pea16b mosfets Next to the SN51285ARUKR shorted , and the Chip Intself was Also shorted , i have removed them and main Power rail IS not shorted anymore , but right Now im still eating for this parts And in checking rest of the board . But pin 14 od the SN51285ARUKR when this chip od removed is shorted to ground Its +5VSUS has 6ohms , And that can not be , i have check mosfets All over the board And i have found ONLY one tahat ís shorted its...

Bad cap

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Shorted internal layer in thé motherboard

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- Channel: Troubleshooting Laptops, Tablets, and Mobile Devices
06-21-2026, 07:50 AM
Lenovo Legion 5 NM-D562 Rev 3.0 – Short on +3VL rail / Need help tracing the short

by GranTisocco

Hi everyone,
I'm working on a Lenovo Legion 5, motherboard NM-D562 Rev 3.0 (2021-05-17).
The original problem was related to the 3V/5V power section. I replaced PU6201 (RT6585CGQW) and PQ6203. The previous short on the 5V section is now gone.
However, I found another problem on the +3VL rail.
With the jumper between +3VLP and +3VL opened:
+3VLP side measures around 2 MΩ and rising, so this side seems OK.
+3VL side measures extremely low resistance, approximately 2–4 Ω to GND.
The low resistance is present with both probe polarities.
I traced...
- Channel: Schematic Requests ONLY!
08-18-2026, 09:43 AM
GTX 1080 TI Gigabyte Aorus low resistance on vmem

by cind12

Hi guys, i was wondering, i've got 9Ohms on Vmem, one of the mosfet was shortet to ground, so i've desoldered hi and low mosfets nad still low res, then i removed all of the memory chips, and the resistance is still low, so did you had maybe a card with that low res on memories, and the card was working fine ?
Removed the U1866Q and still without result, i dont have thermal cam so can't see where is hot spot when incjeting voltage.
The resistance on core is ok 0.1Ohm ((Power 0.8V when on)
Resistance on 12V 4K ohms (Power present when on)
Resistance on 12V PEX 4K ohms...
- Channel: Troubleshooting Desktop Motherboards, Graphics Cards, and PC Peripherals
12-08-2023, 09:09 AM
FNIRSI HRM-10 Internal Resistance Detector AC Lead Acid Lithium Battery Tester Review on some testing of device

by sam_sam_sam

https://www.ebay.com/itm/405035016711

I got this device yesterday and did some testing on some tabbing and some incandescent light bulbs and it seems to work very well from what I can tell but how do I know how accurate the m-ohms section is what can I use to verify it accurately I also tested some li-ion battery cells and this seems to be fairly accurate because I have another tester and they seem to agree with each other

I also checked some capacitors with it that were brand new and seem to show about what I expected to see with my blue capacitor tester so I think it...
- Channel: General Electronics Technical Discussion
04-13-2025, 08:17 PM
PS3 CECH-2001B (DYN-001) shuts down after Vcore rise – VRM debug, no short found

by Elementallion
Hi everyone,

I’m troubleshooting a PlayStation 3 Slim CECH-2001B, motherboard DYN-001, and I’m stuck at a fairly deep VRM-level issue.

I’ll try to provide as much structured information as possible.
🔧 Initial problem

Console behavior:
- Press power → green light for ~1–3 seconds
- Then shutdown with beep and blinking red
- Fan barely starts spinning
This looks like a typical early power fault / YLOD-type shutdown, but I’m debugging at board level.
🔍 Measurements and observations

🔌 Power rails
- 12V rail: stable, no drop during
...
- Channel: Troubleshooting Game Consoles & Other Weird Devices
03-23-2026, 09:32 PM
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