Flashing 'lightning bolt' (located on the right-side display hinge)...???

Heyall...

I hope this is the 'right place' to place this post(???I've posted it 2X now...the 1st post was deleted?..

having an issue with the red-flashing 'lightning bolt' (located on the right-side display hinge) Inspiron E1505 / 6400 :

The 'original' battery lasted only months before dying completely and suspect, I looked into the recall, but mine was NOT listed...I then replaced it with 'an original equipment' Dell battery (which turned out to be used & not  new )...it arrived 1/2 charged, but I never was able to charge the battery any higher and subsequently it ran down to the point it is again: 'A DEAD BATTERY'...

So. (at this point, and for some time now) I have been running the computer on the AC adapter - wih the battery installed (even though it's essentially dead and will not charge) w/o incident, except that I can't use the laptop in any location other than tethered to the AC cord... The red-flashing 'lightning bolt' (located on the right-side display hinge), has never flashed or (even lit-up) before today...rebooting, adjusting the AC input, etc., makes NO difference whatsoever...

I don't have access to another AC adapter (or another battery) w/o purchaing one (or both)...Is there anything that can be done to stop the red flashing lightning-bolt?...(ie. buying a 'new' battery?...or a new AC adapter?...is there another way to diagnose the AC adapter?...I need to keep this system running and really concerned the flashing lightning bolt icon may be a sign that it's on it way out (???), electrically speaking...

If there's a method of testing to see if the AC adapter (& battery) are bad or if there's another issue that could be causing this, I'd appreciate the advice...

Thanks again for the time... Kindest Regards all...

T~
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