Question Laptop fan will not start spinning

[geo_5_]

Hello.

I recently had to reflow my laptop gpu to get it back to being functional. The reflow worked and I then started reassempling the laptop. Everything worked fine but I noticed I forgot to put back a component. So I had to take it apart again. After I reassembled it together I noticed the fan didn't spin. I got no error during post and booted windows.

Things I have tried :

Checking any loose cables.
Checked with bios l. (even did default setting and a hard reset cmos battery)

Checked with speedfan: I get 3000+ rpm and some other time I got 1000+. Though the fan doesn't spin a bit. I think these are false readings.

I changed power settings to default.
I even started a game to see if the fan started then, but nothing.

Finally I replaced the fan with a new one but still the same issue.

Strange thing is that I don't get a single warning /error, not even during post.

Thanks in advance.

 

[helpstar]

the sensor or fan controller might be defective after your reflow process

 

[geo_5_]

Hi thanks for the reply.

After the reflowing process it was working normally. I think I short circuited it because when I started plugging in things I forgot the power on and touched it with my bear hands. Can I tell with a polymeter?

 

[helpstar]

Maybe resetting and/or reflashing the BIOS of the laptop can help

 

[geo_5_]

Tried both but none managed to make the fan spin. Also the motherboard doesn't seem to be toasted or something around the fan.

 

[helpstar]

Which laptop model is it exactly?

 

[geo_5_]

It's an HP pavilion dv7 2230ev. Motherboard model is HP 3624

 

[helpstar]

Did you reapply thermal paste before mounting the heat sink?

Check the connector of the fan, resolder the pins
check the voltage of the pins if possible with a multimeter
check if the fan can spin freely

How hot is the laptop getting? Use coretemp to have a look

 

[geo_5_]

Yes, I reapply thermal paste every time I attempt a fix. The fan works normally to another laptop I tried.

I will check with a multimeter and report back.

I'm really grateful to you for your help.