HP 15-CS3635ND SYSTEM FAN 90B missing components ??

[pcrepai]

Hi, guys, customer bring me laptop with SYSTEM FAN ERROR 90B, fan is not spinning at all !!! As far as I can see someone else tried to fix it, I dont have any boardview, or schematic, but it looks like some components r missing, can anyone confirm it ??

BOARD DAG7BLMB8D0 REV D

Fan itself works fine, Ive also change bios, without any result, does anyone have EC for this board ??

Thanks in advance !!

[SMDFlea]

Re: HP 15-CS3635ND SYSTEM FAN 90B missing components ??

does anyone have EC for this board ??

Thanks in advance !!

Bios and EC requests go here -> https://www.badcaps.net/forum/forumdisplay.php?f=40 .Use the forum search, what you are looking for might already be posted,and if not you can can post your request in a related thread or start your own

.

[pcrepai]

Re: HP 15-CS3635ND SYSTEM FAN 90B missing components ??

ok. I get it . I didnt find any schematic of this board thats why I asked anyone can confirm missing components on this board. (photo HP02).

[JaroTech]

Re: HP 15-CS3635ND SYSTEM FAN 90B missing components ??

Hi, they are both capacitors rated at 220pF 25V, but they have an asterisk which means they may not be essential.

[pcrepai]

Re: HP 15-CS3635ND SYSTEM FAN 90B missing components ??

thanks

[trepachka]

Hey, if you are still experiencing System Fan Error 90B out of the blue, I have an HP 15-cs laptop with the same issue. My laptop comes with 2 identical fans for the CPU and the GPU. Using multimeter, I have found the CPU fan was missing a 3.3V pin. 5V pin and PWM pin were present. The GPU fan had all pins present. Both fans run but I did get the error message. I only have the schematics for this board, no boardview. So, I wound up running a wire from the GPU fan 3.3V pin over to the CPU fan 3.3V pin, about 2 inches long. Now, the error message is gone. Basically, according to the schematics, the EC chip pin 47 is used to probe if 3.3V line is present on the fan and since it was missing, the computer was giving out that error.