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Toshiba T3100e CMOS battery

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    Toshiba T3100e CMOS battery

    I have just acquired a Toshiba T3100e/40 - eBay of course - and it is in rather good operating condition, but of course has a failed CMOS battery. I know the settings to enter in the setup to get it booted, and they work just fine, but I'd like to put a new CMOS battery in it if I can get one.

    Since documentation for these 'laptops' seems almost non-existent, I'm not sure what battery I need.

    I have found 'T3100' CMOS batteries - a 3.6 Volt 2600 mAh lithium battery with 4-pin connector - but I don't know if that is the same as for the 3100e model.

    The question therefore: Is this the right battery?

    I am also interested in any documentation for the T3100e - the user manual for example. I am not finding anything out there, which means there isn't, or I'm looking in the wrong place! I do have the 4-page spec sheet, a sales flyer and what seems to be a technical reference guide with troubleshooting steps, but not documentation that seems likely to have come with the system when new. Is there anything out there?

    Since I'm a newb, my post may be delayed, so hopefully this won't be old information by the time it reaches the forum!

    What a cool machine! Do you have a picture of the existing CMOS battery? The maintenance manual seemed to indicate it was a NiCd, but it's not super clear, maybe they were talking about the main batteries.
    A google image search reveals that at least one person has bodged in a CR2032 with success.

    The wikipedia article has links manuals in the references section:
    Here is the maintenance manual:
    Perhaps you've already found the above.


      It is certainly a very cool machine! Rather heavy to use as a laptop, but a superb piece of engineering.

      The maintenance manual you gave the link to is for the 3100SX - the 386 derivative of the range, which did have battery power, where the earlier 3100 and 3100e models were 286-based, and were mains-powered only. (As far as I know!!)

      I haven't had the chance to take the cover off to look at the old CMOS battery, but the 3100e maintenance manual - which is from the same source - does reference a 2-pin lithium battery connector 'PJ 1' on the motherboard.

      I know I could bodge a CR2032 fix - and for all I know, it might already have had one - but I'd prefer a 'correct' battery if it can be sourced, and the one for the T3100 I found online is only $14, so would be my choice if it fits the space and connectors. The 3100 and 3100e were somewhat different however, but without much documentation I just don't know exactly how different!


        The maintenance manual for the T3100e is at [here]. In that manual, the battery is drawn as item (H) on page 4-17. Page B-1 reveals: Lithium battery of 3.6V and 100mAh.

        Additional T3100e battery info found at [here].


          A CR2032 is not enough juice. I’ve found in both my T5200 and T3100e when using a 2032, the time drifts when the unit is unplugged, almost like the time stops progressing when the machine is powered off. And within about a month or so it will start forgetting the settings completely again, so I’d definitely recommend using a proper 3.6V battery.
          Compaq - It simply works better


            Not quite as simple as I had hoped, but I guess I need to open the computer up to see what's already in there before I order a new one. I'm grateful for the links, and the observation on the CR2032 being insufficient. I wasn't comfortable with going that route with the Compaq, but getting a 'correct' replacement battery for that was much easier since it's well documented.

            The maintenance manual does not make getting access to this battery look all that straightforward, so I may use the Tosh having to press F1 and do the settings and date/time manually for a while yet!

            Thanks for the guidance!