CMOS Battery Madness claims new victim

[parispete]

Being a writer, I own a T21 which I love to bits, but whose CMOS battery has been slowly dying. So being a methodical kind of chap, I downloaded the pdf handbook, bought a new bit on Ebay, and settled down to fit it with my usual laptop fix kit - a set of jewellers screwdrivers, a dental probe with a hook, two pairs of needle pliers, two torches - plus a thing for dewaxing my ears which works a treat for pushing wires around in confined spaces.
I knew the small CMOS battery lived under the main battery, so it looked like a five minute job. HAH.
Then the trouble started
What IBM either didn't know,or forgot to say, is that although it's a simple push fit to connect the CMOS battery's tiny connector, getting the old one out is anything but a simple pull disconnect. To add to the misery, your view is really restricted and access to the submicroscopic plug you want to pull out is just about zilch.
So with the only alternative a full pullapart of the T21, I tried to jiggle these tiny white blocks apart, slowly increasingly my pull on the wires ... until - KAPOW - both leads pulled out. Now I'm really up S**T Creek without a paddle.
So if any fellow sufferer has been through this vale of tears and has any ideas .... PLEASE light me a way out.

[Unknown_K]

I never had any issues removing a T2x battery, you just unscrew the plastic holder and yank it out. What has been an issue is buying aftermarket batteries on ebay which have a slightly different plug on the end that will not for the plug on the motherboard. Since all those batteries are the same I just use a needle to pull the leads of the old battery out of the plug and use the old plug with the new battery (just makes sure you get the color code correct when swapping the plugs, I do it one wire at a time).

[rkawakami]

About the only way you are going to get a good look at the connector is to remove both the keyboard and the keyboard bezel / palmrest.

[parispete]

Yeah, thanks Ray and UnknownK, I think I'm going to try both before I go insane - but first the needle trick. Just because I'm and old fart and no longer take care, can anyone remember (viewed from the top) whether red is left or right into the little white plastic block connector? I have the suspicion it goes to the left. If I make a mistake, I don't think the small voltage in a flat battery would do much damage, or am I wrong here?

[rkawakami]

Here's a close-up of the T23 CMOS battery connector: http://www.kawakami-ca.com/images/02k65 ... 2k6715.jpg (inset photo, left side, labelled "T2x") With the connector's electrical contacts facing up, the red (+) wire is on the left. I would assume that whoever designed the motherboard would have put blocking diodes in the circuit to prevent any problems with reverse polarity.

When viewed from the top of the motherboard (i.e, keyboard removed), the black (-) wire goes on the side where the Ultrabay connector is and the red (+) wire goes on the side where the main battery terminals are. Two more photos:

http://www.kawakami-ca.com/images/t2x_c ... ctor_1.jpg
http://www.kawakami-ca.com/images/t2x_c ... ctor_2.jpg

[ozzymud]

Thanks for the pics. I just got my T20 battery in from eBay today, while transferring the battery to the caddy... I was thinking red goes here, red goes here.... then just as I went to put the new battery into the caddy... brain fart


Your pics let me see which way it went No more error on boot

[parispete]

Thanks, Ray, you're a brick. I'll try the simple way first of just pushing the leads into the two holes, but this will involve a push-in replacement of the red and black wires if this does not work. I have done a deal of damage to the tiny white block connector in trying to get it to come away, so I may untimately have to strip it down to properly get at it.
You seem to have vast experience in Thinkpads, so perhaps you could direct me to a good step-by-step dismantle website for a T21

[rkawakami]

I have not run across any web site that shows a complete (or even partial) teardown of the T2x systems. If you already have the Hardware Maintenance Manual for the T2x system, then that's the best thing you can get. In order to take off the keyboard, you need only to remove two screws: the one near the battery latch and one just next to the MiniPCI compartment. Remove the main battery and push up on the silver area next to the CMOS battery. That's the underside of the trackpoint buttons. The keyboard can then be slightly flexed / bent so that it clears the keyboard bezel. Remove three screws inside the base; near where the trackpoint buttons were, along the edge of the Ultrabay cage and one on the other side of the Ultrabay (holding the hinge cover). You then have to remove almost all of the screws on the bottom; three underneath the front edge (usually covered by small rectangular plastic covers), the CMOS battery (that screw is attached to the keyboard bezel), and three screws near the back panel (the screw right under the DC power jack should not be removed). Then it's a matter is working your fingernail around the edge, between the base and the keyboard bezel and it should come right off.

edit: Corrected for T20-T22 systems and added three screws I missed.

[Majestic]

YouTube has a video posted on the basic disassembly of a T2x that might be useful. The video will at least give you an idea of what Ray is describing.

http://www.youtube.com/watch?v=4dQlLn1GwDk

[rkawakami]

Yeah, leave it to YouTube to have something like this... . I made a mistake in my previous post (I've just corrected it). I described the screws to remove the keyboard based on a T23 (which I've done more of). The T20-T22 systems have the second screw just outside of the MiniPCI area as shown in the YouTube video. Still, you don't need to take out the screw under the DC jack. The keyboard bezel can be removed without doing so.