Should boot with no battery. You can try an external VGA monitor and see if you get video to that. I would be worried that the battery goo got into the motherboard and that needs cleaned or that when you cleaned it you got the main board wet. Let the unit sit a day or so to dry and try again. If it is still dead take the guts out and see if there is any corrosion on the motherboard.

If tere is no picture, then the problem is either cable or video card or PCB of the LCD itself.
Is therean image on external monitor? Does the screen flicker or react anyhow if you move the screen? This could be an indication of a bad cable.
First thing to do is to take it apart, clean and reseat all connections. If it does not help - you probably need to get a replacement LCD.

Bondi wrote:

If tere is no picture, then the problem is either cable or video card or PCB of the LCD itself.
Is therean image on external monitor? Does the screen flicker or react anyhow if you move the screen? This could be an indication of a bad cable.
First thing to do is to take it apart, clean and reseat all connections. If it does not help - you probably need to get a replacement LCD.

Okay, I tried with an external display and still no picture.
I tried the external display with another thinkpad and it worked so the display is good.

I read the IBM manual and it reads that if there is no image on LCD and external display then the problem is with the motherboard.
So it looks like I am going to have to completely disassemble this this laptop and give it a good inspection.

I also checked the hard-drives and they are good and working.

Intel486dx33 wrote:

My IBM 755CD arrived today. I purchased it from eBay NOT working. It turns out it is all intact it just has NOT been turn on in […]
Show full quote

My IBM 755CD arrived today.
I purchased it from eBay NOT working.
It turns out it is all intact it just has NOT been turn on in a long time.
So I plug in an AC Adapter and powered it on.
It started to boot but the screen remained Black.
I could see that the back light in the screen was working just NO picture.

So I opened up the lid of the thinkpad and looked under the hood ( keyboard ).
I could clearly see the Floppy drive, Battery, and Hard drive.
Everything looked good at first but then on closer inspection I could see corrosion by the battery.
So I removed all the removable drives and battery.
The Battery was heavily corroded on the bottom.
So I cleaned the corrosion with vinegar and let it dry.
I then tried to start the thinkpad but it does not post now.
I do not have a battery installed as it is an old battery type that I do not have a spare of and I can't find one online.

Questions:
Is the battery required to boot this computer ?
What do you think could be wrong with this thinkpad ?
It started to boot when I first turned it on just no picture.
I think the display is good. Might be a cable problem ?

Why bother? Everything this old thinkpad can do a iPad can do better.

In my experience IBM laptops are very unreliable you can invest a lot of money in their repair and then just throw it away to trash, or sell by parts.

I had one A21M with bad repair experience, even some Taiwan laptops live longer.

Did you try Fn+F7 with the external monitor?

dan86 wrote:

Why bother? Everything this old thinkpad can do a iPad can do better.

This is not why most ppl here maintain/refurbish/repair old computers. Just because your iPhone does feature quadzillion more versions of Tetris, it's not worth to save this old machine? You sir, are on the wrong forum.

MAZter wrote:

In my experience IBM laptops are very unreliable you can invest a lot of money in their repair and then just throw it away to trash, or sell by parts.

I had one A21M with bad repair experience, even some Taiwan laptops live longer.

It depends on how they were stored, and what model were talking about. And ofc, there is the obligatory IBM rubber coating from the era. Other than that, my ThinkPads have fared very well...

Auzner wrote:

Did you try Fn+F7 with the external monitor?

Yes, I tried that.
It would only "beep" as it changed mode but no video output.

MAZter wrote:

In my experience IBM laptops are very unreliable you can invest a lot of money in their repair and then just throw it away to trash, or sell by parts.

I had one A21M with bad repair experience, even some Taiwan laptops live longer.

Oh, The First thinkpad I bought for personel use was a A21P with ATI Rage Pro graphics. And the display was NOT to good.

jaZz_KCS wrote:

dan86 wrote:

Why bother? Everything this old thinkpad can do a iPad can do better.

This is not why most ppl here maintain/refurbish/repair old computers. Just because your iPhone does feature quadzillion more versions of Tetris, it's not worth to save this old machine? You sir, are on the wrong forum.

I'm fully aware of that. I was making a joke at Intel486dx33 expense. He has posted in the past and quite often too about how his iPad is the perfect PC that can do anything a old PC can do but better.

dan86 wrote:

jaZz_KCS wrote:

dan86 wrote:

Why bother? Everything this old thinkpad can do a iPad can do better.

This is not why most ppl here maintain/refurbish/repair old computers. Just because your iPhone does feature quadzillion more versions of Tetris, it's not worth to save this old machine? You sir, are on the wrong forum.

I'm fully aware of that. I was making a joke at Intel486dx33 expense. He has posted in the past and quite often too about how his iPad is the perfect PC that can do anything a old PC can do but better.

Right, an inside one. My bad, Please carry on.

I recommend to read this thread, could be final reply to your question:

http://www.vcfed.org/forum/showthread.php?693 … r-Light-Flashes

Personal advice for the future: If you see "STRICTLY SOLD AS IS for PARTS/REPAIR" avoid it, unless the seller has a good rating 100 percent and 5-10 sales for all time.

MAZter wrote:

I had one A21M with bad repair experience

The A2x series has a bunch of problems. Stiff hinges that break the plastic, memory sockets that disintegrate and worst of all: GPU on the bottom of the motherboard, which gets hot and the BGA solder balls crack.

I've had much more success repairing a T23 and A31. Won't touch the A2x series anymore, though.

Well, I was hoping it was just a dead CMOS battery or Missing hard-drive. Because I have fixed so many of these old thinkpads and that is all that was wrong with them. I am going to put it away for now as I need to order some parts.
I will try to fix it later. Maybe early next year.