T21 w/o HDD: turns on with dim screen + hangs entering bios

[indi0]

First let me thank you all for having this nice and helpful site. I had worked on several ThinkPad’s (I do Pc Tech support but it’s not my job, It’s a hobby I love) and always been fascinated by the solid construction/design, excellent keyboard and LCD’s on them. I always wanted to have one for personal use but I’m more a man of workstations, I need full workhorse systems for my job (CAD).

The thing is some friend came to me selling his T21 without hard disk, without Ac adapter but he told me everything else was fine, and was very cheap, around $40 usd. I tough, “well if I can’t make it work I can sell the pieces and double my original investment” so no problem… The situation is that I don’t want to dismantle it, I want this laptop running some Linux distro and use it to write a book and my blogs.. I don’t need it to music, photos, CAD, etc. Just something I can write for several hours straight. This T21 is perfect.

Ok the problem for which I need help is as follows:

Today I took the laptop:

IBM THNIKPAD T21 Type 2648 – 8A/U – S/N 78-HC907
800 Mhz P3
128 Ram
Working keyboard
No CD/DVD drive
No HDD
No AC Adapter
Unknown condition mobo
Unknown condition battery pack
Unknown condition almost everything

With me to an IT trading zone here in my city, I was looking for the Ac Adapter so I could start to look after possible problems, before that I had no idea of the internal situation of the lap. Well I get into some ppl that kindly accepted to test the Charger on my laptop before buying it:

I connected the laptop to the outlet, turned it on and it beeped, I immediately recognized the beeps as of memory issues, so we opened the laptop and discovered it was using two SODIMM chips:

1. IBM FRU 20L0242 64Mb
2. COMPAQ 314848-002 (Some sites say it have 64 Mb, others say It has 32Mb)

Both running at 66Mhz!!!!

Well so we replaced the DIMMS with a PC100 512 and turned it on again, this time with no beeps, fan works. But…. The screen is dim, I can barely see the IBM logo, so we hooked it onto an external screen and everything looked perfect. I tried to select the F12 option to try booting it from a USB with SLAX on it.. no response.. Then I tried to enter the F1 bios set up, ok the lap takes several seconds to enter but when it’s working it tells me to wait for the config startup and hangs on there. We tried 3 times: 1 minute then 3 minutes, the last time we were up to let him rest a big time but Mother Nature appeared.

A big earthquake stroke my country (5.5 Richter scale Earthquake in Colombia Google it) all we could do was run outside the building, the power was shut in the area, a neighbor building break in half (no kidding I see it and still can’t believe it) but it didn’t fall over. I took several minutes for us to settle down and enormous braveness to get into the building again and took our things back, I packed the laptop as it was and leave PRONTO!. Civil Defence closed the area. So much for a day I think, fortunately there were no victims and family is ok. : )

Now the place where I can find the AC adapter it’s closed and it’s really hard to find that kind of charger here. So I have no access to a charger to try my own tests and possible repairs, OTOH the charger would cost $60 usd and I don’t want to spend that amount of money if the laptop does not have a viable solution, I mean, this kind of laptop: 700Mhz P3 + 128Mb + 10Gb HDD + used/working cost around $200usd. Remember that I still have to buy the HDD ($30usd) The Ram’s ($40usd).. Maybe the mobo or the LCD if its really damaged.. so it’s a no go. A new mobo if I could ever find it here cost around $130usd.

I ask for your experience. If in the past you have had a T2x with this specific kind of issues combined. Could be two separate problems (mobo and lcd)? Or just one problem that gives me that two symptoms? What would you do if you were on a tight budget? which problem should I fix first? Which are my alternatives? If there is hope I will buy the wall charger and start the process.

Any insights will be really appreciated. Thanks in advance.

Pd: For reference the minimum wage here is $263usd, a Coke is around $60usc.

[SMA]

About the missing backlight on the lcd, I would say that it is most likely the lcd cable.
It is possible to verify if this is the case. Read about it here.

[indi0]

Hi thanks for the help. Well certainly the cable does not look nice. I opened the laptop after writing the post just to check cables. It looks like the cable is well set onto the main board, I haven't payed attention to that cable before so I don't know how it's supposed to look like, I've seen photos and look like it's brown and glossy.. mine its black, not glossy and has some subtle crackling sound if I full open the screen.. As if the cable were being stressed, don't know if thats normal

For the LCD problem I'm leaning more to think that the problem is in fact a cheap or broken cable. Certainly does not look nice (I wanted to take come pics, but camera was death so maybe later I'll post ones) Thank God. I know that cable is cheap and easy to find here.

Now I'm most worried about the hang on the bios set up, any ideas? I forgot to ask If maybe the lack of HDD can cause this.. Also I forgot to point that my pre earthquake tests were done without battery installed.

A LOT of info about LCD problems btw.

thanks!

[SMA]

What is the FRU number on that lcd cable?
These cables are easy to find, but they are not cheap - at least not here.

Before being able to answer about the mainboard, I will have to ask - did you really test with a PC100 512?
I interpret that as one single pc100 512 MB module!
The largest module support by a t21 is 256 MB - and that has to be a low density module.

Testing without a battery is not a problem. The machine is designed to be able to run on ac only.

[RealBlackStuff]

1. IBM FRU 20L0242 64Mb
2. COMPAQ 314848-002

The IBM RAM is OK and runs as PC100
The Compaq RAM you should sell or give away, because it is PC66.
If you use 2 different RAM speeds, the whole system will only run at the speed of the slowest, hence the 66MHz.
So keep testing with just the IBM module, and get another PC100 module of
64MB p/n 20L0264
128MB p/n 20L0265
256MB p/n 33L3070.
Your laptop does NOT take 512MB or higher! (as mentioned above)
Your T21 needs low-density RAM.
Such a 256MB will have 16 chips (8 on each side) of the 16Mx8 variety, and the 128MB will have 8 chips (4 each side).
Anything else will not work.

To work easily on that T21, download the Hardware Maintenance Manual. With that you can take your laptop apart in no time at all, it's very helpful.
If you need any drivers and/or more info about your T21, gohere.

Because of your trying with a 512MB module, you will not get anything on the screen.
Try with just the 64MB and you should see output on the LCD itself, if the LCD, LCD-cable and inverter are OK.
Or see if anything shows up if you attach it to an external monitor.

The AC-adapter should have an output of 16.5V DC and 4.5Amp, with the + in the middle contact of the round plug.

[SMA]

I have to correct a little

The AC-adapter should have an output of 16.5V DC and 4.5Amp, ...

hopefully this is a typo. Should be 16.0V

The IBM RAM is OK and runs as PC100

it will be pure luck, if someone can get a fru 20L0242 to work in a t21. It is rated 66 MHz and will fit in a 600 or a 770.

[RealBlackStuff]

My bad.
Look at the time I posted it, I was barely awake...

16V 4.5A is correct.
And I should have spotted the p/n for the RAM. I DID mention the correct 64MB PC100 p/n though.

Anyway, I hope indi0 will get things going. If not, we are ready to help if possible.

[indi0]

Hi thanks for the replies

@SMA
Yes you should be correct It should have been a 256Mb I have to admit that I didn’t pay attention to that module. It was hard to find it by the people of the store. All I can say is that the lap didn’t beep after installing that memory module and ran to the IBM THINKPAD welcome screen with no issues. It was entering to the bios set up where it hanged.

@RealBlackStuff
About the IBM SODIMM I posted the info that was on the sticker as seen in this pic:



As I was corrected early I was possible that I was using a 256 or 128 MB SODIMM because the screen, in fact, showed the welcome screen just that is dim: dim as it has no backlit; not as if it’s turned off the brightens or contrast. But I still can see image on an external monitor.

Yes I understand I was barely awake too when I posted, hence all the omissions.. sorry

MORE INFO

I checked the connection of the LCD cable, look like it well set into the board, also I checked the Inversor

The FRU numbers are as follow:

LCD CABLE: FRU 27L0519
INVERSOR: FRU 10L1402

I add some pics so you can see the looks of that parts:
WARNING: BIG IMAGES







Thanks again for your time and help.

[RealBlackStuff]

On the last photo you see a screw in a black triangle, left of the LCD cable.
Take that out. It should go in from the bottom of the laptop. (it's not the cause of your problem though).

Did you hit the F1 key to go into BIOS or did the laptop do that by itself? The BIOS 'hanging' could be caused by the wrong 66MHz RAM.

The dim screen could be the CCFL tube for the backlight, that could be gone. But it could also be a bad inverter.
The inverter is the same for all T20/21/22/23, so you could try one of those.
Only the T20 and T21 use the same LCD-cable.
The T22/T23 have a different LCD-cable so you can't try those.
Best of luck.

[indi0]

Did you hit the F1 key to go into BIOS or did the laptop do that by itself? The BIOS 'hanging' could be caused by the wrong 66MHz RAM.

The dim screen could be the CCFL tube for the backlight, that could be gone. But it could also be a bad inverter.
The inverter is the same for all T20/21/22/23, so you could try one of those.
Only the T20 and T21 use the same LCD-cable.
The T22/T23 have a different LCD-cable so you can't try those.
Best of luck.

Hi. After pressing F1 it took like 15 seconds to get into the bios "welcome" but it never got to the bios options it hanged right in there, I never saw any set up like options. I think that if I can try again for more time It will eventually get in the options. I'm not sure that the other memory which was used to test the lap was PC 100 (There were no beeps at all), the lap was not tested with the memory in the pics (PC 66).

The other thing puzzles me is that pressing F12 (To boot from USB) does nothing. I think the bios problem it's the most serious at this time.

As for the LCD I'm thinking too that it's either the tube or the inverter. I don't have any spare LCD so I could test different parts so I think I'm taking the LCD to some repair shop (as soon as they are open again). The good think is that now I know a lot more of the issue so I'm far from being ripoff by non existing/imaginary problems.

Thanks for the help.

[indi0]

I tested the CMOS battery with a multimeter, the battery is death.

[RealBlackStuff]

If you can't find a ready-made replacement, here is all the info about replacing CMOS and how to do it yourself.
http://forum.thinkpads.com/viewtopic.php?t=62311

If the CMOS battery is dead, there will be an error message, that Date/Time is incorrect and/or incorrect checksum.
It should not stop you from booting, nor should it prevent the LCD to come on.
If you get images on an external screen, you have an LCD/CCFL, LCD-cable or inverter problem.
If you take off the LCD-bezel and remove the 4 small screws at the side to take the LCD screen out, check that the cable is properly inserted at the back of the LCD. These can fall off sometime.

[indi0]

Hi

Well today I went to the store and bought the AC adapter, Memory 64Mb PC 100 and the CMOS battery.

Well I'm sorry to tell you that after setting all my components I booted the PC and it tells me that I have a ERROR 0175. I know what it means, sadly I can't know if the lap had a password before I bought it, my friend don't know either. I believe it's not password related as the "lock" icon does not show.. all it shows at boot is (Either pressing F1 or F12):

Code: Select all

...
System BIOS Shadowed
Video BIOS Shadowed
UMB Upper limit segment address: E000
Mouse Initialized
ERROR
0175: Bad CRC1, Stop POST task.


entering SETUP

It hangs there. The repair seems like buying a new Mobo as the unlock here cost almost as the new mobo. And the new screen takes like 75 usd. So, I think I'm going to sell it by pieces.

Or is there any last hope? Is 0175 ERROR always a mess with passwords or could be anything else?

suggest anything as far as I can't sell the mobo I could try anything experimental. I read somewere that cutting the 5th leg of the AMTEL chip will solve this problem but I don't know which is the "5th leg"

BTW ..Thanks anyway ppl you're very kind and this is a very nice forum. All I know is that if it's not this TP .. It will be another one