A20p does not boot, screen black, no beeps (Images!)

[Robbyrobot]

Well, I've done it again... seems like I never get enough of fiddling around with what other people throw away (or sell for a few bucks).

In this case, I've bought an A20p stripped (no HDD, optical drive, RAM or even Network/Modem Combo card, but strangely enough with a good battery) that was described as "defective".

I removed the battery, put a stick of the proper RAM (PC100) in, attached an AC adapter (genuine IBM), and pushed the magic button. The two lights for the battery and standby status lit, the full row of LEDs just above the keyboard lit for more than just a brief flicker, then went off except for the power on LED, and the fan started.

There were no beeps and the screen stayed dark (no faint image that would indicate a bad backlight).

Now, I've already discovered this thread and since the problem seems similar or identical to mine, will check the CMOS battery.

If that doesn't bring about a change, can anybody suggest anything further?

Although mainboard damage is certainly possible, I haven't yet read about this series (A2x) having any "typical" problems like the BoD in the T2x series, the RAM socket problem in the T3x series or or the "flexing" problem in the T4x series, so I continue to hope.

[rkawakami]

External video present?

How about holding down any key (other than F1) and see if you get a bunch of beeps, indicating a stuck key?

I would have also said to pull the modem card out but you mentioned it didn't come with one. Sometimes those cards can brick a system (at least in a T2x they do).

[Robbyrobot]

Thanks, Ray. I'll try both suggestions - plus the CMOS battery - and report.

[phool@round]

Your laptop has similar specs to the T20 sans ATI Rage video chip. I don't think your laptop is displaying the BOD symptoms since it does attempt to power-up albeit with issues.

I noticed in the thread you found nothing was resolved or followed up on by the original poster. Disappointing because they did have the same issue.

Your system is also displaying a very close symptom of the T23's inductor coils where one or both fall off the board or have one leg of two connected. That will keep the video from displaying but the processor fan will come on, the quick flash of the indicator lights and no beep codes.

Sometimes if a coil is off the board it will rattle inside the case. That's simply another quick discovery test you might want to try before opening up the case.

[Robbyrobot]

Sometimes if a coil is off the board it will rattle inside the case. That's simply another quick discovery test you might want to try before opening up the case.

Thanks for the comments, and in fact I do hear a slight noise when I shake the case. However, I'm not sure what it's due to, since there are loose cables in there too (the NIC/Modem combo card has been removed). Probably I'll eventually have to dismantle the computer and when I do I'll check for what you indicated.

Unfortunately, I have also found that the seller removed the CMOS battery as well - which was not part of the agreement - and thus have complained and requested a replacement. So it may take a little time for me to start diagnosing.

[phool@round]

Wow, removed the CMOS.......why on earth?

In that case how awfully generous they were by including the case screws, a bargain!

[Robbyrobot]

Wow, removed the CMOS.......why on earth?

Don't ask me And the seller was only doing a favor for a friend who wanted to get rid of the computer, so he's pretty upset too. At any rate, I've been promised a replacement CMOS battery, so at least that's settled. And I got an extra NIC/modem combo card together with a T21 mainboard I bought via Ebay (cheap, of course ), so I'm in pretty good shape on that score.

Actually, the A20p is otherwise in quite good condition - no scratches or cracks that I can see. Hope I can get it running again.

[dogtag1968]

Your symptoms sound like a problem I had with my R30, try a different stick of pc100 ram. Mine works great after replacing the ram.

[Robbyrobot]

Well, I've got a new CMOS battery in now, have tried holding down various keys, have added a modem/NIC card I had extra from a T21, and have changed the RAM... but nogo: still no beeps, just the normal lighting of the LEDs and fan startup, but the screen stays dark (no signal to an external monitor either). Looks nasty - why does the mainboard have to be simultaneously the most delicate and the most expensive component of these things

Next step will be to dismantle the thing. If I see anything unusual, I'll report again. Thanks for the suggestions up to now.

[phool@round]

I wonder if the processor is cooked. Do you have another processor to swap with?

[Robbyrobot]

Do you have another processor to swap with?

Yes, if the A20p takes the same type of CPU as the T2x series. That'll be something I try next - thanks for the suggestion!

Edit
The CPU is a 700 MHz PIII and uses a heat pad instead of compound to contact the fan. I removed it, put it into a T21 base and it worked fine.

However, in taking things apart, I find that the computer has already been taken apart by some amateur, and several screws are missing - including the two screws that hold the display connector to the subcard.

The more I work on this, the more it's starting to look like a parts computer and less like a project... but we'll see.

[ajkula66]

Bob,

It should be the same processor type as the low-end T-series...good luck with your noble quest...

[Robbyrobot]

Well, I had put this project aside for quite a while to do some other work, but finally had an opportunity to come back to it yesterday.

I decided to dismantle the computer completely to see if I could find anything obviously amiss. Well, I got the display off, the subcard, the CPU and heatsink, the PCMCIA housing and the upper shield. Still didn't see anything obviously wrong.

Then I removed the floppy disk drive and... hey, what's that!!??!

The mainboard under the drive was filthy, there was some corrosion (green color) and the pin rows of a square chip underneath the drive (one of these things with maybe 40 microscopic pins per side) were corroded and dirty on all four sides.

Quite obviously a spill victim, where the spill was never cleaned up and the computer doubtless powered on in that state many times.

OK, it's junk, I thought. Nothing can survive something like that.

Still... oh, what the heck! I decided to at least clean things up, so I got out the cotton swabs, isopropyl alcohol, water and cleaned the whole area, then using a scalpel (Xacto knife) cleaned between the pins on the big chip, then ran a thin wire under the rows of pins to make sure nothing was sticking there. Then I went over everything with isopropyl alcohol again. By this time, the area was fairly clean, not spotless, but at least it looked halfway decent.

Today I decided to go ahead and see if my cleaning had done any good, so I slapped in a CPU, hooked the board up to a port replicator with an external keyboard and monitor, and without even bothering to attach the heatsink (I was sure the board was dead) powered it on.

To my amazement, it powered on without a hitch, immediatelöy showing the IBM logo on the external monitor. I was flabbergasted!

So then I went to the trouble to putting the base back together and checking again. It still worked, and I could get into the BIOS just fine. In fact, when I attached the display, it also started up just fine and gave a bright, clean image.

I wouldn't have believed a board that was so badly and obviously spill damaged would still be operable, but apparently it is, and I'm quite pleased at this success.

The only fly in the ointment is the fact that the floppy drive is not reading diskettes properly - it won't boot from diskette and I get funny noises from the drive. I've removed and replaced it several times, and partially dismantled the drive, but still haven't got it working. At the moment, I don't know whether the problem is the drive or the board, but since I did manage to boot the system with a CD,. I'm guessing the drive is somehow affected. I didn't find any evidence of spill damage in the drive itself, although the damage was immediately underneath the drive and the liquid may have seeped in from the side (no evidence of a spill on the top of the drive or on the keyboard).

So I'll have to look a little further. But the fact that I've managed to get this far is a wonder to me and just goes to show how tough these Thinkpads are. I'll continue this story as soon as I have anything further on the floppy drive.

[Robbyrobot]

Here's an update after I received a new floppy drive (bought at Ebay just before Christmas).

Unfortunately, after several tries, it doesn't appear to work either. I've attached and reattached the flimsy ribbon connectors many times and the floppy still doesn't appear to be really accessible. One time the computer appeared to start to boot - a message from the disk appeared on the screen - but then everything hung and the computer had to be turned off and on again.

One interesting thing: although I can't boot from or access the floppy drive, there is no problem booting from a CD. In fact, I burned the image of the latest BIOS firmware from a diskette on a bootable CD, and updated the BIOS and embedded controller without a hitch. So up to now I believe only the floppy is affected, although I haven't tried to attach a HDD yet and see whether that works.

Now I would like to have a detailed scan of the upper side of an A20p mainboard, particularly the part underneath the floppy drive, to see if my board is missiong anything. I've taken a couple of pictures of the board near the chip that was badly soiled/corroded, and it looks like something might be missing from it where I've added the red circles. Can anyone help here?

[Tad]

Robbyrobot

I compared your photos to a spare A2xx board (12P3288).
The part which you circled is NOT installed on it. The residue on the solder pads in your pix is probably due to something external.
On my board, those solder pads are clean.
An inoperative floppy drive will usually cause a POST error message.

Try booting without connecting the floppy and see if you get an error message, or if it boots differently from when the floppy drive ribbon cable is plugged in.

Good luck... Tad

[Tad]

I would clean the floppy heads with a 'cleaner disk'. I have done this and solved problems with balky floppys.

Tad

[Robbyrobot]

Try booting without connecting the floppy and see if you get an error message, or if it boots differently from when the floppy drive ribbon cable is plugged in.

Now why didn't I think of that? Good idea, I will. I don't think this has anything to do with the floppy itself, however, as I've already replaced it. I have had major problems getting these "el cheapo" ribbon cables properly attached even on other A2xp machines, so that was/is my first thought. But in this case, I've attached and reattached the cables so many times I'm beginning to doubt this has anything to do with the problem.

The thing that's strange is that everything is apparently OK on the machine - PC-Doctor booted from a CD works fine and shows all OK - except the floppy. The chip that was/is so corroded is apparently the sound chip (Crystal), and the sound is OK, so that has nothing to do with this.

Incidently, the HDD connections are also OK. I attached a HDD to the system and it booted just fine.

[Tad]

Since the FDD was involved with the spill, there may be 'stuff' in or under the FDD connector that the ribbon cable plugs into.
With a stiff bristle paint brush and some alcohol or your favorite solvent, you might try to clean the inside of the connector and underneath it where it is soldered to the board.
If you are into micro soldering, you could remove, clean, and replace the connector.

Tad

[Robbyrobot]

Thanks for the additional suggestions. I'll get back to these as soon as I have time... at the moment, I've started working on an A21p that also doesn't show much life and naturally hope to revitalize it too.

Luckily I have plenty of projects, so it never gets boring here.

[Robbyrobot]

I'm not finished with the A21p and also got sidetracked with a T22 that appears to be working rather than defective, but did have an opportuinity to look at the floppy drive I removed from the A20p more closely today...

I have had major problems getting these "el cheapo" ribbon cables properly attached even on other A2xp machines, so that was/is my first thought. But in this case, I've attached and reattached the cables so many times I'm beginning to doubt this has anything to do with the problem.

When I wrote "el cheapo", that was shameless flattery . These ribbon cables are even cheaper than "el cheapo": the ends are simply de-insulated and a strip of blue plastic foil stuck onto the metal foil leads to stiffen them and hold them at the proper distance from one another.

The end that is supposed to be attached to the mainboard had several leads disconnected from the adhesive and bent back, so that they couldn't contact the mainboard connector. I pulled off the blue plastic foil (very poor adhesive), straightened out the leads as best I could - not perfect, but perhaps OK - then had to use double-sided tape to reattach the blue foil, since the adhesive was not sticky anymore.

I plan to re-try the drive in the A20p in the next few days, taking particular care that the leads actually go where they're supposed to.

[Tad]

Bob

I've got my fingers crossed.
Keep us posted.

Good luck... Tad

[Robbyrobot]

@Tad: Well, I meanwhile opened up the A20p again and very carefully and painstakingly attached the old floppy with its repaired cable. I could have saved myself the trouble, since although the connection was apparently OK, the floppy drive really is defective. Made roaring/grinding noises as soon as the power button was pushed and didn't stop until the power was removed.

So then I attached, with similar care, the floppy drive I had bought to replace the original, with a new/used and slightly better-looking cable.

I removed the CPU fan with its heat sink going back to the display to have a clear field to the connector on the mainboard, then attached the floppy drive ribbon cable alone, inserting it deep into the connector. Then I mounted the floppy drive, and only then did I attach the other end of the ribbon cable to the drive. That appears to be the only way to get a good connection.

And to my surprise and delight, the floppy drive was correctly recognized and the computer booted from it without problems. So all the time, the problem was indeed the poor-quality cable and squeeze connection for it on the mainboard.

I didn't touch anything else, put all the screws back, and - next chapter

Now a number of keys on the keyboard are dead, among them F1, F2, F8, F9, Insert, Delete and Fn. This is not a keyboard problem, as two different keyboards (one German and one US) had exactly the same problem, same keys dead.

The interesting thing is that this does not apply to an external keyboard, where all the keys work just fine.

I assume there must be some problem with the keyboard connection, but despite reseating it many times haven't managed to eliminate (or even change) this problem up to now. However, I'll continue and am at this point confident that I'll get things working OK. Just hope there will be no further problems once I get the keyboard sorted out, as I'm getting tired of solving one problem only to be confronted with the next.

Continued soon in this theatre

[Tad]

I'm sure you know this already, but firm downward pressure on the 'Y' key is needed to properly seat the keyboard connector.

HTH.. Tad