Solved [Solved] Rechargeable CMOS coin battery not charging

A

a59303

Hello,

I have gone through efforts to obtain a rechargeable CMOS battery (ML 1220 - Sanyo rechargeable coin - 3V, new) for my HP Pavilion ze2000 laptop. I had previously thought that I just had to replace the battery in the CMOS and I had not gotten to it, mostly because I had to take the thing apart. So at this point I have taken it apart probably five times and replaced the battery three times. The last time was a VARTA ML 1220, that I only later realized was not rechargeable. The original battery in the machine, I believe was a MAXELL ML 1220 (rechargeable). I could not find a MAXELL ML 1220 (rechargeable) NEW, so the Sanyo is what I have now.

I had read elsewhere, it was on the HP site but I can no longer find it, that to reset the BIOS I had to take out the battery for five minutes and then put it back. Now I am operating under the assumption that the CMOS battery has not worked in three years, so why would that be necessary? Suffice it to say that now I have a rechargeable ML 1220 in the machine and the clock still resets at the interruption of power, even for a moment.

So, my question is, does anything trigger the beginning of the charging for the coin battery? I am assuming the battery was shipped without a charge. Is there a period of time I should wait with the laptop plugged-in to charge; with the battery in, without the battery in?

Is there a command that I can use to verify the charging of the coin battery? sysctl? acpiconf?

Thanks for help with this issue,

a5'


I found the original source of my information:
1.2 Resetting the Computer
If the computer you are servicing has an unknown password,
follow these steps to clear the password. These steps also
clear CMOS:
1. Prepare the computer for disassembly (refer to Section 5.3,
“Preparing the Computer for Disassembly,” for more
information).
2. Remove the real-time clock (RTC) battery (refer to
Section 5.14, “RTC Battery,” for more information).
3. Wait approximately 5 minutes.
4. Replace the RTC battery and reassemble the computer.
5. Connect AC power to the computer. Do not reinsert any
battery packs at this time.
6. Turn on the computer.
All passwords and all CMOS settings have been cleared
Click to expand...
I found it in the PDF here: http://h10025.www1.hp.com/ewfrf/wc/manu ... ct=444477&.
 
Re: Rechargable CMOS coin battery not charging

It's unlikely there is anything to trigger charging. Those batteries are low capacity and the demand on them is low that they probably just continuously trickle charge with a very small current. The new battery may be bad or old stock. Make sure it's in the socket the right way, positive side up. Otherwise, consider that the machine is old and it may be time for a replacement. Newer notebooks do not seem to use those rechargeable RTC batteries.
 
Re: Rechargable CMOS coin battery not charging

Those batteries are low capacity and the demand on them is low that they probably just continuously trickle charge with a very small current.
Click to expand...

So, I think your saying that if I wait a day or so with the laptop plugged in, it may recharge or charge.

Otherwise, consider that the machine is old and it may be time for a replacement. Newer notebooks do not seem to use those rechargeable RTC batteries.
Click to expand...

That is the rational solution, although there are a few reasons why I am trying to use this one; not the least of which is that it works for what I need it for. I am just trying to make it a proper installation and running machine.

Thanks for the reply,

a5'
 
Re: Rechargable CMOS coin battery not charging

I found some information: I have to leave the computer on for a while.

Charge the Real Time Clock (RTC) battery
To charge the RTC battery, connect the AC adapter and turn the computer on (both the DC IN and Power LEDs must be green). Leave the machine on for approximately 24 hours to ensure a full charge in the RTC battery. Please note that the RTC battery does not charge while the PC is turned off, regardless of whether the AC adapter is connected or not.
Click to expand...

Not HP, but RTC maybe.

I found it here: http://forums.toshiba.com/t5/Batteries- ... d-p/102055.

- a5'
 
Re: Rechargable CMOS coin battery not charging

I have not succeeded in fixing the problem but I think that it is due to the socket breaking free of the board.


I tried to glue it. This seems safer than solder.



I had conduction on the foreground connection before I put the computer back together but no longer it seems, the time still gets lost.

Just following up,

a5'
 
CMOS-no power, with working battery

Well...

I am at a loss. It appeared that the problem was a broken connection. The connection I made conducts. I get power from the battery (the battery was shipped with power) to ground. I am very amateur, but it seems that should do it. Anyway it still loses time at the disconnection of power.

Does anyone have an idea what I could try?

Thanks,

a5'
 
FIXED!

FIXED!

I left it plugged in (no main battery) for about an hour. Set the time, take out the plug, plug in, time saved.

a5'
 
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