PowerBook 1400 wont charge

[gobabushka]

ok, im well on my way to reconstructing my old 1400 tht got stolen a few years ago. I just found my 2 24mb modules tht I had hidden . My problem is that it wont charge any batteries. It shows that they have a full charge after a few seconds, but when I disconnect it from power, it shuts off. I have tried resetting the power manager, and I have left it sit completely without power overnight. any ideas?

 

[jwmcfarlin]

It could be that the batteries do have a full charge but they are so depleted that a full charge is so little that it's not enough to keep the machine going. What do you know about the batteries? I'm in the same boat, btw.

Best,

John

 

[gobabushka]

i actually know nothing about the batteries, another theory that I have heard is that it could be the pram battery.

 

[Byrd]

Stolen - wha?

Yes, I'd try the usual power manager and PRAM reset - but the batteries are most likely dead and no amount of hardware trickery will get them to come back to life.

JB

 

[dudejediknight]

Assuming it runs fine without a battery using the power adapter, my guess would be the battery's cells are too old and worn out to take a charge. You could always try the battery in a known good machine or a known good battery in that machine (to rule out some sort of problem with either the laptop or that specific battery)... but I'd put my money on the battery just being at the end of its life. It sounds like the battery is even too far gone for something like Battery Amnesia to try and recondition it to at least hold some sort of charge.

Considering how old the laptop is now... I highly doubt anyone is still making 'new' batteries for it. And even if someone had them, they're probably old stock that have been sitting in a warehouse for years and would be way past their prime. Some people claim that putting a completely dead battery in the freezer helps, but I've never tried that and can't recommend it.

Really, the only option left (assuming it is indeed the battery that's the problem) is to possibly re-cell the battery... either yourself or by paying someone else to do it for you. An internet search will turn up more than one step-by-step guide on how to do it, but it sounds VERY dangerous, so it's definitely one of those 'at your own risk' deals. I've looked into doing it myself, and it really sounds like something that's not for the novice or for the faint of heart, and is definitely best left to the skilled experts.

By the way, I wish I had those memory modules for my PB1400. Since the PB1400 uses special modules that only fit that model, I've yet to see anyone selling them.

 

[beachycove]

A flat backup battery would almost certainly not cause this behaviour (it's not called a PRAM battery). In fact, though you do need a backup battery for "real" use, the machine will likely function well enough for tinkering purposes without one. However, there might just be life in the original cells, but they take days and days to charge and that can only happen if there is a viable main battery already charging. Occasionally serendipity strikes with these things.

The real trouble is the main battery, but because these are NiMh cells, there are some things you can try.

1. Stick them in the freezer for a day or so, remove, let them thaw and dry, and then recharge (google NiMh, freezer trick and dendrites).

2. Get a copy of Apple Battery Recondition (in fact, with a stock System install, it ought already to be in the Apple Extras or Portables folder) and cycle the cells a good 8-10 times, with some overnight periods plugged in. You can sometimes bring "dead" cells up to a 45 minute or so charge through steps 1 and 2 alone.

3. Battery Amnesia is a Shareware utility that could be used instead of #2.

4. Repack the battery with fresh tabbed cells of identical size. Would not cost much to do. $25?

5. Repack the battery with a couple of Radio Shack AAA battery holders and off-the-shelf normal AAA NiMh cells, copying the number of cells, the wiring and the arrangement of the fuses/ sensors in the original battery pack. AAA cells would fit inside the case and will have roughly the capacity of the original cells (at somewhere around 900-1000µA), so the software controlling them (in the Power management system that you are resetting) will know what to do with them. Higher capacity cells are a bit hit and miss in these old machines, so I would not pay any price premium for them.

 

[gobabushka]

thanks everyone for the suggestions. I am gonna try the freezer trick. I thought it was still called a pram battery even though it is rechargeable. What is it called, because i'm curious?

 

[beachycove]

It's called a backup battery.

 

[gobabushka]

thank you!

 

[ClassicHasClass]

beachycove's recelling suggestion is pretty easy to do with 1400 batteries. Just make sure you keep the little circuitry piece (when you crack the pack you'll see it inside; reconnect it the same way to the new cells).

 

[jwmcfarlin]

Beachycove that's brilliant. Thanks, I have a set of 1400 batteries that I am looking at setting up that way, though the BTI-branded packs are made of a brittle sort of plastic that doesn't react well to trying to open them.

Best,

John