Resurrection Challenge: T20 fan spins only at startup

[jarrody2k]

Hey folk,

I have a T20 which has been lying around for some time. Last time I checked it was having heat problems because the heat monitor would get around 70-80 and then my laptop screen would either blank or I would get a freeze.

Recently I tried putting some thermal paste on the cpu to see if it was the wear on the rubber that was causing the overheating... but just today I started up with the keyboard off and watched the fan.... pretty much as it passes BIOS the fan goes off... never to come on again.

I watched mobile meter again as the temperature crept up and got close to 70... so I start blowing on it... I get it down to 50.... let it go... it climbs.

Is there *some* way I can force the fan to be on always... in either hardware or software? Preferably hardware...

It's pretty crazy... all that's stopping this laptop from working is just that a little inexpensive fan isn't turning.

I have seen plenty of older forum posts on this when I search Google and seems to be a problem for a lot of people:

http://zurich.ai.mit.edu/hypermail/thin ... /0218.html
http://zurich.ai.mit.edu/hypermail/thin ... /0246.html
http://zurich.ai.mit.edu/hypermail/thin ... /0008.html

If anyone has clues, I would be glad to hear.

Jarrod

[Temetka]

Yep there is an easy fix.

1. Go to www.ebay.com
2. search for T20 CPU fan
3. Bid and win
4. Wait
5. Install new fan
6. Move on with your life
7. Send me a big fat check, or asian model. Whichever you prefer.

[jarrody2k]

Have you actually witnessed this problem before on a T2x and resolved it like this, or are you just being smart?

How do you know that it isn't because the fan isn't getting enough power?

How do you know if it isn't a problem with the fan speed regulation circuitry? (assuming there is some)

The fact that I can stay around in BIOS and watch it spin forever proves the fan can spin and will spin as much as you want it to.... it just won't do it when Windows starts to boot... or thereafter.

So it does suggest the software can control the issue... or a side-effect of the boot process causes a malfunction of the hardware. I would like to bypass any control of the fan... have it go all the time... or somehow fix the software part of the equation.

Just in passing, I did install a fan stated as "in working condition" from Ebay and both fans did the same thing.

Jarrod.

[Temetka]

Never experienced the problem myself.

However with the cost of parts being so cheap, it is definitely something I would try.

Then I would break out with a multimeter and google (to look up the electrical specs) and go from there. Starting at the end of the circuit path and working towards power.

[jarrody2k]

I'm pretty sure my dad has a multimeter in his garage. I have no experience with tracing these sorts of problems before. I was hoping there was a known hardware remedy so I can just follow instructions... or get my dad to replace a part or solder something back in place.

But if I am to try to track this down, are there any DIY guide to doing this sort of thing that you can point me to? Would appreciate a little push in the right direction.

Cheers,

Jarrod

[rkawakami]

Download a copy of PC Doctor from here:

IBM site (diskette version)

or here:

.ISO image (CD) on my site

Create the bootable diskettes or CDROM, boot the laptop with the media, click on the Diagnostic menu, then the Other Devices sub-menu and select the IBM Thermal Sensors and IBM Fan tests. That should tell you where the problem is.

Going out on a limb... I'd say your problem is the Thermal Sensors. As the fan spins up at power-on time but does not afterwards, the thermal sensors may not be reading correctly or their signal is not getting to the fan.

[iMav]

I'd be interested in knowing if you get the same symptoms with a live CD.

[jarrody2k]

Cheers for the ISO. I lost my ultrabay cd drive when moving last time, so I will source another. When I do I should be a little closer to solving the mystery... I hope!

Jarrod.

[rkawakami]

Here's a link to a post that I made about creating the bootable PC Doctor media:

http://forum.thinkpads.com/viewtopic.ph ... 478#210478

There's some stuff about memtest86+; ignore it as it does not apply to your problem. The original site which hosted the .ISO file has gone bye-bye, therefore I put a copy up on my site.

[jarrody2k]

Nice work... looks pretty thorough! Shame I can't run this tool from Windows. I have a diagnostics download from when I last tinkered with it, but when I run the steps in the autoconfig by hand, the pcdr.exe tells me its not registered for my machine!

Now I guess I will have to find a ultrabay drive just to test whether the laptop is fixable! Though I understand the necessity of having diagnostics without any OS interference, still... a pain hehe.

But cheers again... I only see new ultrabays on Ebay. Will keep looking for a cheap one and hopefully I should have one in a couple of weeks and will let you know how I go.

Thanks again,

Jarrod.

[larryb]

See my post this Forum on 04/03 regarding fan operations.

I had my PCB doing the very same thing, got a new fan on Ebay and guess what.

IT STILL DID THE SAME THING!

So I modified the Motherboard.

Larry