Chosen Solution
It looks like the whole problem was the main battery. I have finally received two new batteries and this computer is working well. The original battery appeared good from everything I could see. The LED indicators on the back showed all lights lit. The charger shows green. The coconut battery program shows everything looks good on the battery. However, when I tried to use this battery in a second computer, that computer exhibited the same symptoms as this computer. So, the final solution appeared to be the main battery. In the process, I reset the PMU and replaced the PRAM battery. These other steps may have contributed the final solution. (Note: The old PRAM battery measured something like 4.1 volts on a voltmeter. I’m guessing the original PRAM battery was not bad) (Note 2: Remember the second computer I tried using with this computer’s battery? It’s working fine with a new battery installed) Thanks for those who contributed.
replace the pram battery. Using a computer with a dead pram battery can lead to unexpected machine behavior.
Try cleaning the battery contacts, they might be dirty, therefore preventing a solid connection.
I reset the PMU and that has made a world of difference! It’s been working pretty good for about a week. However, it has still shut off without warning or any apparent reason about 3 times. I have ordered a PRAM battery. We’ll see if that makes a difference.
