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IBM Thinkpad T40 - No display issue

by Xternalit / November 9, 2008 3:49 AM PST

Hello peeps. My lappy went "dead" on me sine now. The lappy powers up ok but no display. Id also changed memory just to make sure all is well but same no display. Iv also connected my lcd to the vga port of the lappy and still no display. Can someone please help me? Im a technical person so I want to fix it. Please dont tell me to replace the motherboard, thanks

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RE: IBM Thinkpad T40 - No display issue
by Xternalit / November 9, 2008 4:49 AM PST

Before I get into the motherboard components, I got 1 long beep and two short beeps. Does that mean the video section is damaged?

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I spoke too soon
by Steven Haninger / November 9, 2008 4:54 AM PST

If this was a desktop, I'd say you had a base memory memory problem. There are beep codes for missing video cards in PCs as well. You might, as mentioned in my other message, visit the Lenovo site get the service manual. As well, you can possible get an explanation of the beep codes there.

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Check here
by Steven Haninger / November 9, 2008 4:56 AM PST

Looks like it could be the display or RAM

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Try external display first
by Steven Haninger / November 9, 2008 4:51 AM PST

Plug a monitor into the port and see if it works. If so, this about rules out the everything but the display and it's CF power inverter. If your finding is that it's in the display or related circuitry, you can order the necessary parts and repair it yourself. If you want to try the cheapest first, the CF power inverter is the easiest. You can either go to the Lenovo site and look up FRU parts by your laptop's full model number or you can open the screen and get the numbers from the parts themselves. Don't get these from Lenovo. You can do a google search for IBM replacement part suppliers. I recently fixed my wife's T42. After a local repair shop gave her an estimate of $900 or more with no guarantee, I did just what I am recommending to you. I went with the inverter (converts low voltage to high for the CF tube) and that didn't work. I then went for the screen and that fixed it. Getting these apart is a trick but, if you go to the Lenovo site, they are kind enough to provide service manuals for these laptops in Adobe format which you can download. The only problem with this is that you probably cannot return parts that you try but don't work. I got luckly and maybe you will too.

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by Xternalit / November 9, 2008 5:24 AM PST

Iv connected the VGA port to a monitor and nothing shows. What is the name of the device that is not working? What area, on the motherboard, I can look to find the damaged device?

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Does your keyboard have a toggle function
by Steven Haninger / November 9, 2008 5:34 AM PST
In reply to: RE:

I know the T-42 uses the Function & F7keys to toggle between the laptop screen and an external monitor. Make sure that's not the issue first.

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by Xternalit / November 9, 2008 5:36 AM PST

Iv tried that. I dont think thats the case.

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One more dumb question
by Steven Haninger / November 9, 2008 6:06 AM PST

When you say "no display" do you mean no backlight or just no evidence of startup? If the CF lights up, you can usually see some evidence of it especially by darkening the room. If you get a glow from the screen in an unlit room, this starts to point away from the display itself though it doesn't eliminate it as a suspect.

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Bad surprise
by Xternalit / November 9, 2008 6:31 AM PST
In reply to: One more dumb question

The display is completely pitch black. Iv pulled the lappy down completely and saw something that I nearly curse bad words. I saw a burnt component. Id love to post a picture but the "owner" took away my digital camera. To describe it: small brown-rectangle. What is that? A resistor?

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Picture of Burnt Device
by Xternalit / November 9, 2008 7:36 AM PST
In reply to: Bad surprise
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Basic identifiers
by Steven Haninger / November 9, 2008 8:42 AM PST

While you've taken a nice photo, I cannot tell exactly what has happened but it doesn't look right. Components marked with a "C" mean capacitor, "R" mean resistor and "Q" will mean transistor and CR is a diode. Any of these can fail either by themselves or because of another component in the circuit. What I see almost looks like moisture related damage. At least one resistor and one cap look to be unhealthy. As well, it's possible there's been damage to circuit board's traces and lands. Any recent spills? This isn't something you can fix on the dining room table. Your first post said not to ask you to replace the main board so I will oblige. That model is old now though you can find these used. You should still be able to recover your data easily enough by using an external enclosure or an IBM/Lenovo "ultrabay" adapter in another similar laptop if one is available.

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by Xternalit / November 9, 2008 8:47 AM PST
In reply to: Basic identifiers

As I said before, that picture is not of my motherboard. I dont got a camera to show u my board. I searched the internet and found a picture where Im having the problem. On my board, "A" is burnt/damaged. So im asking, what is "A"?

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Sorry but I missed that
by Steven Haninger / November 9, 2008 9:14 AM PST
In reply to: RE:

seeing the red tracings around other components. The "A" as you mentioned, I thought looked like a decal on the board. But if it's a pointer you placed there, all I see is what looks like cut off leads from something mounted to the other side of the board. It could just be attached wires. But, if the epoxy is burned in this area, that's not good. When this happens, raw carbon is a by product an it's conductive. The increased current flow accelerates the damage.

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Let me try again
by Steven Haninger / November 9, 2008 9:20 AM PST

I'm having problems finding the A. I see a red box with what looks like an arrow. That could be an A, I suppose. I also see, to the lower left, a scribbling of what might be an A. It has an arrow pointing to a circled component. Is this what you mean? If so, that would be a capacitor.

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A better look at picture
by Xternalit / November 9, 2008 6:51 PM PST
In reply to: Let me try again
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That's a better description
by Steven Haninger / November 9, 2008 8:05 PM PST

These still appear to be capacitors. I cannot tell what their rating is but "farads" are the term used for capacitance. These small ones are probably uF or pF numbers. It's possible the bodies of these are marked somewhere but you'd have to unsolder a good one and look under magnification. Since capacitors block DC current, a blown one indicates and internal short has occurred. This might or might not take out the cap alone. In any event, you'd need to pull the component to see if it's value is present and readable. Finding a replacement may not be easy.

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by Xternalit / November 9, 2008 8:19 PM PST

Thanks for the help, Steven. I dont know how I'll find the rating. I'll hope and pray that someone has the same board like mine and knows the value of the capacitor.

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I looked at the picture
by R. Proffitt Forum moderator / November 10, 2008 1:39 AM PST
In reply to: Thanks

And that's the sort of flash over damage I see when an energized circuit touches something. It does not indicate the cap is bad.

I'd be looking at other issues on the board.

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But, as he said, that's not his board
by Steven Haninger / November 10, 2008 4:58 AM PST

but another one like it. On his, he said item "A" was burnt. I'm sure you're well aware of the distinct odor that accompanies such failures. I definitely agree that replacing the cap isn't a guarantee that it will be fixed. It went for a reason. It was taken out by another component or it didn't die without taking company with it. If he's lucky, it just arced inside and opened up quickly without taking out damaging another part of it's circuit. Still, if the epoxy in the area has become carbonized, the prognosis is poor.

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I read that too.
by R. Proffitt Forum moderator / November 10, 2008 5:24 AM PST

But those capacitors are so robust that short of hitting it with a hammer I never have found a burnt one. I offered what I suspected THAT picture was showing and if they can't supply THEIR picture then we are left to offer what insight we can.

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He's posted the same picture on another site
by Steven Haninger / November 10, 2008 6:02 AM PST

and noted his obsession with fixing it. It would seem that the board would have to come out anyway to examine it thoroughly. It's no harder to put in a known good board than one that's iffy. I'm not sure how the OS deals with MB swaps in laptops though.

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No Clue Of Device
by Xternalit / November 10, 2008 6:03 AM PST

So I guessed that no one can tell me the rating of what is "A".

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by Steven Haninger / November 10, 2008 6:16 AM PST
In reply to: No Clue Of Device

and I doubt Sams can help either. If this was me and I just had to have this fixed, I'd look for a replacement MB. Keep in mind you'll still have a laptop that's past it's prime.

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Linux Purpose
by Xternalit / November 10, 2008 6:31 AM PST

Its for Linux purpose only. Nothing more. I may have a friend that has one around his room somewhere. Ill see if I can get the capacitor off his and see what happens.

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One more option you can consider
by Steven Haninger / November 10, 2008 6:33 AM PST
In reply to: No Clue Of Device
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I'll Fix It Myself
by Xternalit / November 10, 2008 6:39 AM PST

Thanks but I think I can do it myself. My friend has a T30 somewhere, Ill see if I can take out the cap thats on his board and put it on mine and see what happens.

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"A" is ...
by taughannock / November 21, 2008 2:01 AM PST
In reply to: RE:

a 1210-10 surface mount ceramic capacitor

capacitance value unknown because there is no 2 charachter marking that I can see on the top of the cap and it's not yours anyway as you say (just a photo)

You will need to remove the cap (quicly heat up side to side) with a soldering iron and then measure between the terminals with a capacitance meter

Note if your cap is toast it was likely caused by another device failure like a transistor, IC, or diode. They do not usually burn up by themselves and are typically used just for filtering.

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no display
by racavas / February 25, 2013 2:07 PM PST

When i try to boot up the IBM T40 Laptop it on but no dispaly. Fan sppining full time. no hddincator is on when it s on

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As this is a 4 year old discussion.
by R. Proffitt Forum moderator / February 26, 2013 1:48 AM PST
In reply to: no display

It would be best to use the answers that are here and then create a new post. Why? Because you want the best replies.

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