My Dell inspiron 3542 laptop had a very good battery life(>6 hours), but today morning it showed an error message saying "Battery has experienced permanent failure and needs to be replaced." I updated the BIOS from A3 to A10, but it didn't help! The PC starts only if its plugged in and the battery charge is constant at 82%. What should I do?
It's quite possible your battery did suffer a failure; the Lithium-Ion chemical reaction may (which produces electricity) have finally broken down.
First thing to try is to run Dell's diagnostics. When you first power it on, press F2 to run the ePSA Diagnostics & see if any failures occurred.
Have you tried powering the laptop on with the power cord and battery, then once it's loaded removing the power cord to see if it stays on?
Another thing to try: remove the power cord & battery from the laptop, then hold the power button down for about 10 seconds. Then reconnect the power cord, power it on, then reconnect the battery.
From here, once it's on, you can try removing the battery again to see if it stays powered on or leave the cord connected to see if the battery begins charging.
Hope this helps!