Problem may be;
1) Video Cable:
A) May have a loose connection on the motherboard side, or back of LCD screen side.
B) May be damaged.
2) Display Assembly:
Specifically the screen Inverter, or LCD screen.
Primer:
An LCD screen does not produce light.
http://solutions.3m.com/wps/portal/3M/en_US/Vikuiti1/BrandProducts/secondary/optics101/It needs an additional light source.
A Backlight is the additional light source.
A Backlight (Present technology) can be a CCFL, (Or dual CCFL's), or a series of LED lights.
The IBM T43 series of Notebook PC's uses a single CCFL.
Cold Cathode Fluorescent Lamp.
Similar to Fluorescent lighting used in homes, and businesses, but on a MUCH smaller scale.
(Average size of bulb is;
1) Width: 2mm. {Slightly more than 1/16th of an Inch }
2) Length: A little shorter than the LCD screen is in height.
Basic example,
http://www.ebay.com/itm/14-1-XGA-CCFL-BACKLIGHT-LAMP-IBM-THINKPAD-T42-T43-/270965162524?pt=LH_DefaultDomain_0&hash=item3f16c8421c )
The screen Inverter converts power from the laptop for the LCD screen, and Backlight.
90 PERCENT OF THE TIME the fault is the screen Inverter.
Primer over.
Example of Inverter,
http://www.batterycentury.com/lenovo-ibm-thinkpad-t43-inverter-p-186266.htmlThe thin plastic 'frame' in front of your LCD screen, is the LCD Bezel.
(Goes by several names, depends on manufacturer.
Display Bezel, Display Panel Bezel, LCD Bezel, LCD Front Bezel, etc.)
Behind it, and located at the bottom of the LCD screen, is the Inverter.
IBM ThinkPad T43 series of Notebook PC > Service Manual (Free),
http://www.tim.id.au/blog/tims-laptop-service-manuals/#toc-ibmlenovoGo down to the line that begins with ThinkPad T20. (T20 in blue)
Scroll across, click on - T43
[ This is a PDF file. The computer you are using now has Adobe Reader on it, which uses PDF files.
After you click on the file name { T43 } it may take up to 30 seconds, before the first page comes up ]
A) ALL power removed. Remove the AC adapter (Charger) and Battery.
B) It would be BEST, if you would wear an ESD wrist strap. Have it's alligator clip connected to a good ground source.
(Electro Static Discharge)
Average price of an ESD wrist strap is $3 to $6.
One example,
http://www.radioshack.com/product/index.jsp?productId=2103245C) Use a multi-compartment container for the various screws you will remove.
Label each compartment for the area the screw/s come out of.
SOME screws look VERY similar to other screws. Do NOT mix them up.
1) Check the connection of the Video Cable TO the motherboard, and TO the back of the LCD screen.
NOTE*
The connection MAY look to be plugged in tightly, but in reality it is not.
Physically make sure the cable is plugged in tightly.
(Especially at back of LCD screen )
You have to remove the Display Assembly from the laptop, in order to properly access the video cable connection, at the back of the LCD screen,
NOTE*
PDF file page number, and service manual actual page number, Do Not match. When I refer to a page, the reference will be to the PDF file page number.
Go to Page 121 in the Service Manual, for units that have a 14.1 Inch LCD screen.
Page 126 for 15 Inch.
Motherboard Connection:
Laptop open, looking at the LCD screen; The cables on the Left are Video. The cables on the right are for the Wireless Antenna.
LCD screen connection:
Disassembly of LCD Assembly starts on Page 154.
Page 167 shows the video cable, and connection.
LCD flat panel cable = FPC. Also known as Video Cable.
On Page 121 you will see a component removal list, listed in order of removal.
You can click on an underlined subject, to go directly to the chapter that deals with it
To remove the LCD Assembly, (Display Assembly), you have to
remove the Keyboard, then Keyboard Bezel. (Palm Rest)
Once the Keyboard Bezel is removed you have direct access to the motherboard connection side, of the LCD cable. (Video Cable, or for IBM - FPC)
Check the connection. Tight or loose, you still have to check the connection at the back of the LCD screen. (LCD Panel)
1a) Check for damage to the LCD cable.
If there is obvious damage to the outside sheath of the cable, there may be damage to the tiny wires inside the cable.
Even if there isn't obvious signs of damage, the tiny wires inside may be stretched/broken.
Use a multimeter set to Ohms, and check the continuity of the wires, inside the LCD cable.
{ An economical, yet good enough for this test multimeter, can be purchased for as little as $8 to $12. Available in a multitude of stores. An auto parts store is but one example. Analog or digital is fine }
2) LCD cable checks out it's on to the screen Inverter.
Make sure this small circuit board isn't damaged. (Pulled wire/s)
To test a screen Inverter requires a sensitive multimeter. Read fairly expensive,
http://www.fonerbooks.com/test.htmSomething the average consumer does not have.
For this reason, the ease of accessing it to replace, and the usual low cost, (Compare to an LCD screen), the unit is usually just replaced.
Parts changing I know, but you have to use what is available to you.
Or see what a computer repair shop will charge to test the unit.
[ NOTE*
An LCD screen, and a screen Inverter are a MATCHED unit!
When replacing make SURE you get the right part ]
3) Screen Inverter checks out it's a bad LCD screen.
NO, your graphics chipset is FINE.
For additional questions, or clarifications, please post in a Comment.
Regards,
joecoolvette
×