Fan Error x 2

[Guinness19]

Hey everyone,
So my T43 recently became a paperweight because of the oft-mentioned fan error. I knew it was coming as the fan was making even uncharacteristically more noise (if you can believe it!) until it finally stopped spinning completely - thus fan error.
So I ordered a replacement and put it in (with helpful advice to the many related posts!). Unfortunately, I'm still getting a fan error when I turn it on with the new fan. I haven't completely reassembled everything, but when I plug in the keyboard and on either AC or battery power the new fan won't spin - just a loud beep and "Fan Error." The connector to the mobo seems well seated. And I've tested the fan on a separate power supply and it spins like a dream.

It may be worth noting that I was initially having some trouble disengaging the heatsink from the GPU and initially thought I just needed to take more stuff apart (before reading posts on how to do that online). So in the course of my repairs, I've had the thing completely apart - mobo disconnected from the lower chassis. I'm fairly certain I put everything back the way it's supposed to be.

Anyone have any idea what might be going on here?

Thanks in advance!

[Guinness19]

Update: So if I plug my power supply into the back of the jack where fan meets mobo, fan spins and laptop starts up normally. So by giving my fan an external power source, everything seems okay. Maybe I fried something on the mobo power supply to the fan? I also tried starting up the computer with no fan plugged in and couldn't find a voltage across any of the pins on the fan connector.

[richk]

There is a fuse on the motherboard that your original fan might have blown. Most repair shops do not repair surface mounted parts

moved to t4x forum

[Guinness19]

I found the fuse that connects power to my fan as richk suggested (with help from the link in poshgeordie's sig). Sure enough it was kaput. Before getting messy with the soldering iron, I shorted it out with an alligator clip and sure enough fan ran smoothly.
I fixed it per richk's suggestion by piggybacking another fuse on top. It wasn't easy with my big fat radioshack soldering iron but it works! Everything boots up great now. Thanks for your help guys!