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HP Forum Archive 20

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HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #1 Posted by Anthony (USA) on 15 Mar 2011, 6:12 p.m.

Hi, everyone. I ordered a humble HP 95LX and received it today. Well, I put two new 1.5V AA batteries and a new 3V CR 2032 coin cell, and every time I turn it on I always get the "Main Battery Low" message. I go to SET UP and to the System menu and the battery status is approximately one-fifth dead. Any suggestions why it's almost out? Thank you. :)

      
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #2 Posted by DeboT on 15 Mar 2011, 6:37 p.m.,
in response to message #1 by Anthony (USA)

Have you tried a second set? You may just have a dud battery.

            
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #3 Posted by Bill (Smithville, NJ) on 16 Mar 2011, 3:07 a.m.,
in response to message #2 by DeboT

Do you have any PCMCIA memory or other cards installed. If so they can cause a voltage drop on turn on.

Which battery brand are you using? I remember that on my unit, Duracell batteries would not provide the high turn on current while Everready didn't exhibit the problem. With Duracell, I would get the main battery low every time I turned the unit on.

Of course now, I just use Lithium AA batteries.

Bill

      
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #4 Posted by robert rozee on 15 Mar 2011, 8:25 p.m.,
in response to message #1 by Anthony (USA)

hi,

this is a known problem with the 95lx, mostly (as far as i can tell) affecting 512kb models. i've never encountered a 1mb model with this problem and assume that by the time the 1mb models were in production HP had made component changes to prevent it.

i am afraid the only solution is a hardware one - replacing a defective tantalum capacitor with a ceramic one. you can find a short item i wrote on the procedure here, including pictures:

http://www.hermocom.com/en/knowledgebase/hplx/95lxlowbattery

you need to find someone nearby who is handy with a soldering iron, and able to follow the pictures :-) HP did repair defective units for some time free of charge, but that was way back in the 90's.

FYI, i much prefer the 95lx over the later 100/200lx, simply because of the far more readable LCD screen.

cheers, rob :-)

            
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #5 Posted by Anthony (USA) on 15 Mar 2011, 10:14 p.m.,
in response to message #4 by robert rozee

Thank you all. I don't have access to a soldering iron, but when I find a friend who do, I will definitely get it fixed then. Until then, do you think I could keep using my HP 95LX without having the batteries run dry after just days of use?

                  
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #6 Posted by robert rozee on 16 Mar 2011, 7:48 a.m.,
in response to message #5 by Anthony (USA)

the messages do not affect power consumption, and are purely an annoyance. the only problem will be that you won't know when the batteries are really empty, so you'll need to save frequently and have a spare set handy for when the unit stops running.

Edited: 16 Mar 2011, 7:51 a.m.

                        
Re: HP 95LX - New Batteries But Still Shows "Main Battery Low"
Message #7 Posted by Anthony (USA) on 16 Mar 2011, 3:48 p.m.,
in response to message #6 by robert rozee

Thank you, that really puts the message into perspective. Okay, I'll make sure to save constantly and carry with me batteries. Thank you. :)


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