Thinkpads Forum

Hi, this is my first post in this great forum!

I recently started to use OpenBSD 6.0 in my venerable Thinkpad T60 (1951-FDG) and I have to say that it has a great performance for its age. In fact, I have been using it in the last weeks as one of my main programing platforms. I was missing the 4:3 screen.

Nevertheless, there is a problem in my T60: the status bar leds are not working at all. In addition the laptop does not sleep after closing the lid. I've seen in the forum several posts regarding similar problems but in most cases the screen was also dead. In my case the screen works perfectly at 1024x780. Thus, I guess that there may be several causes for this issue:
- The inverter is defective (but the backlight is still working...)
- Dead fuse in the mobo (is it possible to deal with that without soldering?)
- Defective LCD-mobo cable
- ...

Does anybody know how repair it?
Thank you very much.

Welcome to the Forum.

For any repairs, download the (illustrated) manual from the HMM link at the top of this page.
It'll tell you how to replace a faulty inverter, and what part# to replace it with.
If it's a fuse, there are 2 possibilities:
- fuse F7 (type 433003) immediately to the right of the LCD-connector on the motherboard
- fuse F3 (type 434003) immediately above/left of the power-connector on the motherboard (F3 is TINY!!)
Measure the fuses with a multimeter, set to continuity/beep.
But before you do so, remove battery and AC.
You will have to remove the motherboard from its chassis.
You will need to piggy-back solder a new one on top of the old one.
If that's too much work, ask someone else who can do it for you.
Or buy another motherboard (I have some for $20 shipped within CONUS: http://theboardroom.info/stock.html )
Yours is the 14.1" Standard 4:3 with Intel graphics.

RealBlackStuff wrote: [...]
If it's a fuse, there are 2 possibilities:
- fuse F7 (type 433003) immediately to the right of the LCD-connector on the motherboard
- fuse F3 (type 434003) immediately above/left of the power-connector on the motherboard (F3 is TINY!!)
Measure the fuses with a multimeter, set to continuity/beep.
But before you do so, remove battery and AC.
You will have to remove the motherboard from its chassis.
You will need to piggy-back solder a new one on top of the old one.
[...]

Thank you!

I will try to borrow a multimeter in the next days but if any of those fuses is blown I'm done because my soldering skills are not that great. On the other hand I would imagine that if some of the fuses are dead the complete LCD would be dead... I'm just trying to be optimistic.

Do you know if it is possible to piggy-back solder using conductive paint?

Thanks again.

PD. I've read in the forum that its uncommon to see defective inverters but it is quite common to have bad fuses.

By design, fuses are supposed to give up their lives so that they might prevent more circuit damage from occurring. However, I have seen semiconductors (transistors, ICs, etc.) blow up before the fuse(s).

By "conductive paint", I'm assuming that you are thinking about painting a (wide) trace between the ends of the fuse(s) that may already be damaged. While this would not require any soldering equipment or personal skills, I would NOT recommend that action. Fuses are physically designed to allow only a certain amount of current to pass through them before they blow (within a certain, given tolerance). Conductive paint could be good enough to allow current flow but you will have absolutely no idea how much. You would be a risk of damaging the motherboard more than what exists now.

When dealing with blown fuses, you should try to understand what made them blow out in the first place. If you do not know what caused it and you have not taken steps to prevent it from happening again, replacing the bad fuse with a good one could result in another blown fuse.

rkawakami wrote: [...]
By "conductive paint", I'm assuming that you are thinking about painting a (wide) trace between the ends of the fuse(s) that may already be damaged.
[...]
When dealing with blown fuses, you should try to understand what made them blow out in the first place. If you do not know what caused it and you have not taken steps to prevent it from happening again, replacing the bad fuse with a good one could result in another blown fuse.

No. I was thinking about getting a new fuse and using conductive paint in order to "solder it".

You're right, I should look for the causes of this mess. I still remember when it happened (about 5 years ago): it was in a crappy hotel with a terrible electrical installation, so I guess there was a voltage peak in the net and boom... Nothing strange happened, no smoke, no funny smell... just stopped to work.