Question about IBM ThinkPad T21 2647 Notebook
Where can I find the schematic diagram for the power control/battery charging circuit for an IBM T21 Think pad?
SOURCE: IBM Thinkpad T21 LCD problem
Am I understanding your correctly? - the monitor of your T21 is working intermittently? Please, let me know if I've misunderstood your description of the problem.
If the issue is w/ the monitor, ....
And the symptoms are intermittent and change w/ opening and closing the cover (monitor) then there's a good possibility the problem isn't w/ the monitor itself rather it's w/ the cables or wiring going from the monitor to the mainboard. If that is the case, whether it is repairable w/o replacing the monitor will depend upon the cables and/or wiring involved.
It would make sense that an issue like that was caused by worn or damaged cables/wiring as those are the parts of the monitor that would've been subject to wear and tear over time.
I recommend you disassemble the monitor from the laptop and carefully inspect all the cables and wiring that run between the monitor and the laptop.
I will see if I can find a service manual online for you that will step you through removing the monitor.
If it does turn out that the problem is w/ the monitor itself or that the monitor's wiring or cables cannot be repaired, you can search the Internet for another Thinkpad T21 that you can salvage parts off of. (eBay would be one good place to look.) You can try finding just the monitor but I think you'll stand a better chance at finding a T21 that is being sold for salvage.
In the interim, you should be able to connect an external monitor and use the computer w/ it for now.
IF you connect an external monitor and the symptoms persist, then the problem isn't w/ your monitor at all. Be sure to post back here and let us know if that is the case, too.
Please, let me know if this response was "Helpful" or a "FixYa" for you or, of course, if you have additional questions, etc on this topic.
If I did not answer your question satisfactorially, plz, b4 assigning a "Thanks for Trying" or lower rating to my "Solution", let me know. I may have misunderstood you or the problem you are experiencing. In any case, I will work w/ you until your problem is resolved or diagnosed. I promise! :)
Posted on Apr 05, 2008
SOURCE: IBM Thinkpad T21
This is a common problem with the T20 series Thinkpad. The problem is with the power management chip. Unfortunately, you will have to replace the motherboard to fix it. Since these are a bit on the older side, you can get a motherboard off Ebay at a reasonable price.
Posted on Aug 05, 2008
SOURCE: IBM T21 Thinkpad
Here are the solutions ive gathered for this problem:
IBM has finally given me a fix for the T21 I am working on for a
customer. I asked them "What if it doesn't work, then what. Their
response was "GAURENTEED to work". Here it is:
1.) Unplug the power cord and the battery.
2.) Press the 'Power' Button 10 times repeatedly.
3.) Then hold the 'Power' Button down for 25 seconds.
4.) Put the battery back in and plug the power cord back in.
5.) Should power up right away.
This did work THIS time on the machine I have in front of me. I hope
this works for all of you. If you have any other questions, please
feel free to email me and ask any questions
Oh and just one more thing to help you out.
This problem is caused by an overcharged capacitor (supposedly) and
the error ONLY occurs IF you leave the laptop plugged in too long with
the battery in. If you ONLY plug it in when you are using it, then it
should not overcharge. And actually I would suggest that you unplug it
about 20 min or so before you are done using the system.
I have been a IBM Thinkpad T20 user for last 3+ years and I think it
is an very sturdy system that it's been working non-stop for such a
long time with not a single problem even after so much of abuse it
went thru in my baby's hands......until last week when it just wont
boot up. Then I found this post online....I tried the refrigerator
option also to no avail. Finally I just removed the battery and AC and
let the system sit for a 2 days in a cool place near window. Third day
I plugged in battery, plugged in the AC, and voila, it comes up fine.
Right now I am backing up all my files and I'll keep you posted if it
experiences a boot problem again. If I don't post again, assume it's
all working good again !!
Bottom line is that it could be the overcharged capacitor in my case
and letting it sit alone discharged it completely.
Good luck to you!
I have the same problem, and i fix it. Well no fix but now in few
seconds i can start notepad when i want to. My battery dead. Without
the battery, you can start if you hold down the power botton while you
get in/get out quickly the ac connector several times .Try it!!!!
I think the intelligent battery or same cheap condensator in the power
module is the problem (so when you connect the ac power connector you
can hear the charge of it).
you can restart without problem but if you switch off you will need to
repeat the process to start the notepad.
I have a T22 that won't power on. After removing the AC power cord, I had to repeatedly (as fast as you can press it) press the power button until it powers on. I was not able to do a normal shut down, it would just hang. So with the battery removed and the AC plugged in pull the AC power cord.(Try to do it when the hard drive light is out!)I have cycled thru several power ups with no problems after doing this.
Hope this might help somebody else.
I would love to know which capacitor is being affected on the motherboard. this way you could install a momentary switch with resistor to ground to drain the capacitor.
Thanx to all the authors of these solutions
Posted on Jan 10, 2009
Tips for a great answer:
Sep 16, 2010 | ASUS F5RL-X1 Notebook
Sep 10, 2010 | Computers & Internet
May 06, 2010 | IBM ThinkPad T23 2647 Notebook
Sep 21, 2009 | 1997 Honda Accord
Mar 08, 2009 | IBM ThinkPad T23 2647 Notebook
Jan 29, 2009 | IBM ThinkPad T40 2373 Notebook
Jan 14, 2009 | IBM ThinkPad T20 2647 Notebook
Jan 10, 2009 | IBM ThinkPad R40 2897 Notebook
174 people viewed this question
Usually answered in minutes!