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1400 Battery Discharge Issue
Posted by: LaPorta on 2024-06-16 18:45:38
I've been more and more aware of this strange issue affecting my recapped and restored 1400. The machine gets very confused about batteries and discharge time. After a few minutes of use (in this case, it was 25 minutes), I get the "reserve power and screen dimmed" message when it is obvious that the battery is doing just fine. To test and quantify the issue, I installed a copy of myBattery to be able to share some data. In the first photo, you can see me getting the message while the battery indicator in the menu bar obviously shows a good charge. She second photo shows the info in myBattery also showing a good charge and relatively linear discharge:

Picture 1.png

Picture 2.png

Regardless of that message, the machine hums along quite nicely for a long time (in this case, one hour approximately):

Picture 3.png

Next, the machine goes to sleep and refuses to start again when giving me the "No power remains" message...when it is obvious that the battery is fine and definitely not discharged. I missed the massage, but right when I plugged the machine back in and woke it up, here is what the battery stats showed:

Picture 4.png

Somehow, the machine thinks the battery is completely dead, whereas the battery monitor can detect that it is at least still half full. It is still giving good wattage as well. I have been good about reconditioning the battery with the Apple reconditioning utility. This is one of two packs I have rebuilt (within the last 3-4 years) - the machine does this with both of them. Do they really wear out that fast? Or, is there something wrong with the hardware of the machine?
Posted by: LaPorta on 2024-06-17 13:00:41
Any insights would be helpful.
Posted by: Snial on 2024-06-17 15:35:19
Any insights would be helpful.
Didn't @Phipli rebuild a PB1400 battery? Does it have the same problem?
Posted by: TimHD on 2024-06-27 23:20:50
Did you run the battery calibration tool that these PowerBooks have?
Posted by: LaPorta on 2024-06-28 07:36:51
If you mean the battery recondition, then yes, I’ve done that every few months or so.
Posted by: LaPorta on 2024-06-28 07:37:26
If you mean the battery recondition, then yes, I’ve done that every few months or so.
Posted by: TimHD on 2024-06-28 18:08:22
I wonder if that ‘Troubleshooting’ tips in the System Source guide might point to some possible causes/fixes - have been trying to revive an old PB1400 battery myself (else might look at one of those Battery Rebuilds) but not seen that warning (yet!)…

The below seems to suggest that the Low Power warning might come on for something other than (a true) low battery warning - though that last one looks like a “if all else fails, replace logic board’... There’s additional suggestions, also copied below.
IMG_0710.jpeg
There’s also these ‘Battery Verification’ suggestions:
IMG_0711.jpeg


IMG_0712.jpeg
IMG_0714.jpeg
IMG_0713.jpeg
Posted by: LaPorta on 2024-06-28 18:33:42
I'll definitely verify with the voltmeter: not sure why in the world I didn't think of that to begin with. I will verify either charge or discharge. If they are still good, I'll try the PMU reset. If that fails....well....I've been putting off changing the logic board. The floppy drives no longer work in the machine, and I have no idea why. Logic board might be going.
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