Re: How do you change the clock/control panel battery on a 170?

Hello James,

Am 16.02.2024 um 01:26 schrieb James H. H. Lampert via MIDRANGE-L <midrange-l@xxxxxxxxxxxxxxxxxx>:

See my previous message about today's surprise revival of our V5 "fat" 170.

Congrats on that!

After the second IPL, I did some further poking around in SST, and found indications of a failed clock/control panel battery. And that it had failed before last November's incident when it refused to power up.

Does anybody know what kind of battery a 170 takes?

It's a CR450 button cell. It has been this type of battery since the P03. Don't know about newer machines, see below.

Or how to change it out?

I just searched for IBM 9406-170 main planar in Google and had a look at the resulting pictures. The battery holder is located at the very bottom right of the board.

A friend of mine replaced it once and I dimly remember him telling that the battery holder was obstructed by part of the case (holder for the rear end of cards).

For that matter, what about an E4A?

I don't know. But Google helped again, for checking if it failed for you:

https://www.ibm.com/docs/vi/power6?topic=frus-tod-bat

I was unable to locate the TOD battery just by browsing IBM documentation. The E4A I have access to isn't physically close, so I can't take a look either.

For the record: An empty clock battery had never caused me any trouble besides the irritating 0000BBBB SRC. I observed this condition on many older machines, CISC and RISC, predating the advent of rack-mounted Power5's. My experience with machines ≥ Power5 is very limited.

:wq! PoC