IBM PS/2 Model 70 with small motherboard May have PSU issue

[thegenerallee86]

I have an IBM PS/2 Model 70 with 60MB drive and I bought it and it has problem with ether the HDD or PSU but now I am leaning towards PSU More because when I got it, it would not even turn on with HDD plugged in but I took it out and will boot to the error screen where it shows Red not ok and CMOS Battery Bad, Keyboard, and Time/Date wrong error code. But after a few times of taking it apart and checking voltages which looked good according to the schematics, and also cleaning the connections with Rubbing alcohol and qtips, now it will shut off even with the floppy drive once it is done checking the memory and goes to try the floppy it shuts off immediately?

[wierd_w]

How long did you wait for the isopropyl to dry?

 

Let it fully and completely dry out before doing any further power ons.  Remove the battery completely as well.

 

You should also inspect to make sure the battery did not leak. It might not be readily apparent, but it's always important to check. The lithium batteries used in PS/2 systems can have that kind of failure, and it is not pretty.

Edited August 13, 2022 by wierd_w

[thegenerallee86]

4 minutes ago, wierd_w said:

How long did you wait for the isopropyl to dry?

 

Let it fully and completely dry out before doing any further power ons.  Remove the battery completely as well.

 

You should also inspect to make sure the battery did not leak. It might not be readily apparent, but it's always important to check. The lithium batteries used in PS/2 systems can have that kind of failure, and it is not pretty.

not very long, and also let it sit for a while after and still doing it, The battery definitely didn't leak either this thing is very clean whoever had it before me either kept it very clean or cleaned it very well it looks almost brand new even the PSU.

[wierd_w]

this may be useful for you.

 

https://ardent-tool.com/docs/pdf/ps2-hmm.pdf

 

It contains information about the PSU, and how to test it. (starting at page 138)

Edited August 13, 2022 by wierd_w

[thegenerallee86]

1 hour ago, wierd_w said:

this may be useful for you.

 

https://ardent-tool.com/docs/pdf/ps2-hmm.pdf

 

It contains information about the PSU, and how to test it. (starting at page 138)

Thank You and I have already checked and just did a double and noticed that this according to that all the pins that are 5v when I tested them they are all grounded and believe they should not be?

[thegenerallee86]

Well an Update I got a new psu and now it boots to basic and doesn't shut off immediately when trying to access the floppy drive though it doesn't even try to access the HDD, I think that is because the CMOS Battery is dead and needs a new one and also need to create a reference disk as well because of the battery being dead for so long.

[wierd_w]

Yay!

 

That's a good sign.  Yes, you will need the setup/diagnostics disk to reconfigure the system options before you can properly use it.

 

If this is an MCA based system, you will need ADF disks for all the cards as well. There are archives of those floating around.

[thegenerallee86]

42 minutes ago, wierd_w said:

Yay!

 

That's a good sign.  Yes, you will need the setup/diagnostics disk to reconfigure the system options before you can properly use it.

 

If this is an MCA based system, you will need ADF disks for all the cards as well. There are archives of those floating around.

Luckily there are no add on cards to deal with just the HDD and floppy drive and onboard things.

[wierd_w]

Well, if you ever find that you need them, there are places on the net with large archives.

 

Like this guy's:

http://www.mcamafia.de/mcapage0/adflist1.htm

 

Or these people's:

http://ps-2.kev009.com/eprmhtml/epradf/adfall.htm