• LAPTOP DELL PRECISION 5550 - grzeje się pu400

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#1 LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Tadzaiorek 14 October 2025, 16:11
Witam, mam uszkodzoną płytę LA-J191P
procesor : SRJ8J - Intel Core i9-10885H
GPU : N19P-Q3-A1
LAPTOP DELL PRECISION 5550

Po podłączeniu na termowizji grzeje się układ pu 400 oznaczanie 3H=7J
grzeje się również ut7
pobiera płyta 3W

Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Google Adsense [BOT] 14 October 2025, 16:11

#2 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Vogelek23 14 October 2025, 17:40
Device marking 3H=xx to układ RT6585BGQW. Zmierz rezystancje na pinach 3 i 13 tego układu.

#3 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Tadzaiorek 15 October 2025, 07:18
pin 3 1,39 KΩ
pin 13 275 K Ω

#4 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by matic 15 October 2025, 07:25
- Measure the resistance to ground on pin 5 of chip UT7.
- Measure the resistance to ground on the cathode (- pin) of diode RTCD2.

#5 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Tadzaiorek 15 October 2025, 08:48
UT7
Image
RTCD2
Image

#6 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by matic 15 October 2025, 09:52
Tadzaiorek wrote:RTCD2
[ Obrazek ]
You have a short circuit to ground on the power rail "+RTCVCC_R". Perform a short circuit test described here (lesson #3) on the cathode (- pin) of diode RTCD2. For a short circuit test limit the voltage to 3V.
The MEC KBC chip is very likely damaged.

#7 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Tadzaiorek 15 October 2025, 10:25
tak, kbc się grzeje jest tam kbc : mec5107-LJ

#8 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400  [SOLVED]


by matic 15 October 2025, 10:57
So the KBC chip is damaged almost for sure.
First of all remove it from the board and remeasure the resistance to ground on the cathode (- pin) of the diode RTCD2. If the resistance is high (in the kΩ range or greater), solder the replacement KBC chip.

#9 Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Tadzaiorek 15 October 2025, 12:11
Zdjąłem układ KBC, zmierzyłem rezystancję, była wysoka, wymieniłem układ z innej płyty głównej i laptop się już uruchamia. Dziękuję bardzo za pomoc w rozwiązaniu problemu.

Re: LAPTOP DELL PRECISION 5550 - grzeje się pu400


by Google Adsense [BOT] 15 October 2025, 12:11

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