Solved! Dell Inspiron 1720 Fan Not Running (unusual issue)

[Noobsaibot21]

Hi All,

I am hoping someone can help me with a very strange issue I am having with my laptop (an old one but eager to keep it going). Specs (of interest) for reference:

OS: Windows 10
RAM: 4GB
GPU: NVideo 8600GS
CPU: Intel T9300

In short, the fan is failing to run at any time and it is overheating as a result. I have tried:

* An alternate fan and the issue is the same. Absolutely no movement in either case (both have been fully cleaned and spin freely), I have had them checked for voltage and BOTH have the same, correct readings. In addition, I have tested both with a 9V battery and both work just fine in this case.

* Alternative RAM sticks. No change

* My old, stock CPU. No Change

* A replacement MOBO. known to work. Unbelievably, STILL no go

It's very puzzling and have spent less than €70 troubleshooting so far however, I really dont want to spend more on just trying things. The only remaining things I can think of..... Well, the only things that have NOT been replaced are:

* The power cable and battery (happens on both so unless i'm just super unlucky, I dont know. Aside from the fan, everything is perfectly fine until it all freezes

* The CMOS battery (very unlikely I know but it's one of the four unchanged)

* The GPU (possibly. It does run quite hot (hotter than the CPU at this time as far as I can tell/allow). The GPU pipe does eventually lead round to the fan area as well as the CPU's one. But would the GPU actually stop the fan spinning/getting instructions somehow?

* Some FAN Bios setting which is NOT set in BIOS but rather set via Windows

Anyone able to shed some light? Aside from the above, cant think of what else to try :S

Thanks in advance
Noobsaibot21

 

[webworkings]

Have you tried just replacing the fan?

 

[Noobsaibot21]

Yes, that was my first thought. Same with a replacement which is confirmed working

 

[webworkings]

Have you tried testing to see if the fan is actually getting power from the motherboard?

 

[Noobsaibot21]

Can you advise what steps I could try to test that?
This was one of my thoughts so got a replacement mobo but still the same. If there is another way to check this, I can try

 

[webworkings]

If you replaced the motherboard as well, then that should have resolved the issue.

In this case, then I am at a loss.

 

[mjslakeridge]

I'm not too familiar with laptops, but does the cpu cooler fan get it's power from a wire coming from the cpu fan header on the motherboard, like in a desktop? If so, have you checked the connections on both ends of the wire? Maybe wiggle the connection around a bit while the laptop is on to see if the fan briefly comes on.