Thinkpads Forum

There is a fuse labeled "F7" right next to the LCD connector on a T61 motherboard that seems to control video output. I have one that is blown after an LCD break and nothing appears on the screen - no LEDs no picture. The designation on the fuse is "P", which I think means 1.5amps, but Im not sure. I have another good board (an R60 that has the same fuse in the same location) but I don't want to remove one from the good board. I have another R60 that is dead, but its F7 fuse has the designation "000", so I'm not sure if that one is OK to use. If it matters, the ones with the "P" fuse have discrete graphice (one ATi, one Nvidia) and the one with "000" has integrated graphics. Any info would be appreciated.

Thanks

Does the "P" fuse look like this one:

http://www.littelfuse.com/data/en/Data_ ... se_437.pdf

If so, then the code stands for 3 amps.

edit: And this might explain the "000" part:

http://www.koaspeer.com/resistors.asp?part=16

Basically a zero ohm resistor that also has a current limitation.

Yes. Thanks. I now think both the blown "P" fuse and the "000" fuse on the junk board are both 3 amps. (different manufacturers???) After I posted the question, I pulled some of the black plastic off the junk board and found printing that said F7 3 amps, 32V. There is the same printing on the other boards as well. It would be nice if they printed the stuff near the fuses. The "000" thing is an open circuit (blown). A 0-ohm resistor with current limitations sounds a lot like a fuse.

Hello richk,

I think I blew the same fuse when I disassembled the bad Samsung LCD panel in my T61p. Don't remember exactly wether it was marked P or F though. Its the for the power supply of the inverter board, this means the LCD was still working but without backlight and also the status LEDs were dead. Without disassembling the entire Thinkpad I fixed it temporarily by applying a layer of conductive silver laque on top of this SMD fuse.

It is still working but I would like to replace the fuse someday nevertheless. These SMD parts are often hard to come by in small quantities. If some sort of group buy could be arranged I would be joining it.

@701C: Here in the US, both mouser.com and digikey.com usually sells parts like this in single unit quantities. What kills you is the postage, even within the country. You might want to ask around at http://www.thinkpad-forum.de/ and see if anybody there knows of a distributor that will sell you just one part.

701C wrote:Hello richk,

I think I blew the same fuse when I disassembled the bad Samsung LCD panel in my T61p. Don't remember exactly wether it was marked P or F though. Its the for the power supply of the inverter board, this means the LCD was still working but without backlight and also the status LEDs were dead. Without disassembling the entire Thinkpad I fixed it temporarily by applying a layer of conductive silver laque on top of this SMD fuse.

It is still working but I would like to replace the fuse someday nevertheless. These SMD parts are often hard to come by in small quantities. If some sort of group buy could be arranged I would be joining it.

Sounds like the exact smae issue I'm having with a R61 > http://www.thinkpads.com/forum/viewtopi ... =5&t=80159

Did you ever do a permenant fix? Or is the laptop still running without the fuse?

I pulled one from a junk board