Acer Aspire 5535
Battery will not charge.
Mains power keeps the laptop running without running the battery down, but battery does not charge.
If mains is unplugged, the laptop runs on battery (but runs it down).
System Tray icon shows battery state, but indicates mains is not connected (when it is).
PSU voltage checked with a voltmeter. 19.1V
Voltage also measured on motherboard, so plugs, sockets and wiring are all OK.
Tried another PSU with exactly the same result.
Looks like the BIOS is failing to recognise the PSU and therefore not using it to charge the battery. I know that some Dell laptops do this, but they show a warning message to explain the problem. There is a chip in the Dell PSU which provides identification, and some non-genuine PSUs have a chip fitted in an in-line adaptor.
Having read about BIOS problems that might be related, I looked for a BIOS update. The existing BIOS is 1.04 and no update available. I downloaded the 1.04 version to re-flash in case of corruption, but the update refuses to run unless the mains is connected. The mains IS connected, but it isn't seen so I can't update!
The CMOS battery was low, but not dead. I replaced it.
I charged the laptop battery from a bench power supply, taking care not to overcharge, and the laptop is working fine so long as it is always on mains to prevent the battery running down.
Edited to add that laptop will not power up without battery installed, or with very low (3%) battery. That's why I charged it to 77% on a bench supply. Battery has good capacity and runs down slowly as would be expected when mains is removed. System Tray monitor is showing the battery state correctly. Laptop has always been used with mains connected - effectively using the battery as a UPS.
Has anyone seen any similar problems, or have any suggestions?
