Help With Fried Laptop (Lenovo T410s) Fan Connector From a Momentary Short

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MC012

Joined Apr 4, 2021
4
Long ago, I was doing a small project with a lenovo t410s when I accidentally shorted out the laptop fan port's pins for a split second. So, whenever the laptop turned on, it displayed "fan error" and the cooling fan did not work. It also immediately shut down following the error. I tried modding and putting a different fan but no luck. With multi-meter, turned out there is no power at all in the fan connector when the laptop turned on. Its a 3 pin connector and none of the pins received any voltage.

Now that I have some time on my hands, I really want to at least attempt in fixing this issue. If nothing, I am going to be throwing it out anyways. So, when I posted long ago in Tom's Hardware, a mod responded that I "knocked out the point where the power is delivered to the fan via the motherboard. You will now need to inspect the board around the CPU fan connector inch by inch to verify which power delivery module you knocked out."

I tried to find the schematic and I may have found it on this drive link. On page 71, there is a schematic regarding the fan connector (I think). I see a fuse in the schematic but Idk where it is on the actual board I have here (sorry for zoomed/blurry pic). Anyways, maybe I am wrong about the fuse.

Could someone please please help me in identifying the problem and solving it?
(And Sorry!!!! if this is the wrong place to post)
 

Ya’akov

Joined Jan 27, 2019
9,165
There is a fuse there, and it could be the problem, but your photo is so bad I can't tell which component is the fuse.
 

Ya’akov

Joined Jan 27, 2019
9,165
Hi, this is honestly the best photo I could take, currently around 4:30 AM.
Best guess is this is your fuse. Check for continuity with a DMM. Check in diode mode in both directions in case it is a diode. If it is open then it is your fuse and it is dead. If it conducts it may be your fuse but it is not dead.

1617525009553.png
 

sagor

Joined Mar 10, 2019
910
My "guess" is that the fuse is the larger rectangular device just to the lower left from the "F4" silkscreen. That device seems to have a wide trace, possible a power trace. A 2A fuse would likely be a bit larger than nearby components, again a guess...
But Yaakov might be correct with that small white chip since it seems to have a small "burn" mark on the lower side...
 

Ya’akov

Joined Jan 27, 2019
9,165
My "guess" is that the fuse is the larger rectangular device just to the lower left from the "F4" silkscreen. That device seems to have a wide trace, possible a power trace. A 2A fuse would likely be a bit larger than nearby components, again a guess...
But Yaakov might be correct with that small white chip since it seems to have a small "burn" mark on the lower side...
I believe that is a cap, as shown in the schematic.
 
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