laptop shuts off

Hello
Okay, I have a laptop issue...after being on for about 30 to 60 minutes it shuts down, and will not power back on unless I unplug the power cord and remove the battery and then put them back in. there were two fans that were not working, so i replaced them, and the issue persists. after looking at it the the fan closest to the back still does not come on unless it is temp activated and I have just missed it. this one was also replaced, and it did get plugged in and everything. It is a compaq presario 2500
as an afterthought, I do not even need to be using the laptop for it to shut off, if I boot it and just let it sit, it shuts off too...
Thanks
Hoffy

 

Have you tried running it on AC with the battery disconnected?

 

Nitrowing. Many makes of laptops require the battery installed to run on the mains, even though the battery is stuffed. My old laptop is one of them.

@hoffy628. How old is the battery.
Have you ever done the discharge/recharge maintenance on your battery.
There may be a "ring around the bath line" above which a battery will not charge.
Can't remember the technical term but someone will reply. Bazza

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