Thinkpads Forum

Hi all i have a Lenovo T61 i have put a new screen in it and invert er but still no back light
but can get back light to work by only half plunging in the invert er ??? can any one help me with this

"half plugging the inverter"??? what exactly does this mean?

Without more info, I'd have to say you have a bad jack on your ribbon cable. I have the cables if you need one, but without testing it myself I can't tell you for sure if that would fix the problem, or not...

If i plug the inverter in one end and not in the other end it works
the plug on the inverter is a long plug and only plugging one end in
it works fine.
i have put a new ribbon in it also have no lights on the inverter only
wi fi light works both inverters are the same so i have ruled that out
both ribbons are the same so that it not the problem if i plug a a
external screen in it works fine so its not the graphics card there
are some fuses on the motherboard i thinking it could be one of them
that is my next test but if you have ant idears that i could test for let me
now thank you

If you swapped out both cable and inverter, and with both the 'old' and the 'new' pair you have the same results, you could also have a bad LCD. or the cable is not inserted properly into the LCD.
Please give us some more information, like TYPE of T61 (on a sticker on the laptop bottom, looks like TYPE 7363-4AU).
What are the P/N or FRU numbers on your LCD cable(s) and inverter(s) and LCD(s)?

The system board definitely has the ability to control the backlight, so you might be onto something with a bad fuse, but that might be optimistic, it could very well be a more serious system board fault. If you have another T6x series computer that you can plug the lid into, that should tell you if the problem is in the lid, or not.

Thank you both for that information i don't think it is a bad screen as it will work as i said if i only plug the inverter half way in that is just one end as soon as i plug it in all the way it stops working but with a light you can just see what is on the screen so i am thinking it is a fuse on the motherboard the (Type 7661-11M)
thank you for your help if you know where i can get the diagram of the motherboard and the fuses i think it will help me to ether fix it or rule out that as the problem
Yours Colin

This website should give you the location of the fuses...

http://thinkwiki.de/T61_Sicherungen

However, I wouldn't try to remove the fuse/s, rather piggyback a new one on top, but even doing that will require some skills in micro soldering, so good luck.

Hi thank you i have done this and it is working fine thank you it was i bit fiddly to solder the fuse but i got there
and all good
AGAIN THANK YOU
Kind Regrades Colin S

Glad I was able to help, and very glad you were able to fix your laptop. I just hope the reason for the fuse failure doesn't re-occur.