Question Thinkpad E490 not booting up with Battery connected. Advice please?

[iceman95]

My laptop is not turning on when the power cable is connected. The charging indicator doesn't light up, and a brief message saying 'Critical low battery error' shows up for a second, along with 3 loud beeps.

However, if I remove the battery and connect the laptop to the charging cable, it is working just fine, albeit a bit slow. Does this mean that there is a problem with the battery, and it needs to be replaced? Are there any software checks I can do? Or extra drivers to be installed?

I had taken my laptop to a local PC repair center last week, and the technician there had suggested that there might be a problem with the charging port, and the entire motherboard might need to be replaced. However, the charging port works just fine when the battery is removed, and the laptop is able to run solely on AC power. I think the problem is with the battery, and I just want to be sure before buying a new one.

My laptop is a Lenovo Thinkpad E490, approximately 1.5 years old. It was acting a bit strange before the problem as well. The battery was taking a long time to charge, and drained out pretty quickly. Even when the charging cable was disconnected, the indicator still showed that it was charging.

Is there anything I've missed here? I think the battery needs to be replaced, but I'm not completely sure about this. I'd love to get suggestions on what to do. Thanks.

 

[AlHuneke]

I have a few concerns:

• Not sure why it would be running more slowly when on external power only. Perhaps you can borrow another charger and see if it responds the same way. If you have a voltmeter and can access the power jack pins, you can measure the charger output voltage when the computer is off, on and with the battery installed. You should not see much variation--maybe a volt or so.
• The battery may be bad but inside the laptop is the circuitry that supplies the charging current to the battery there could be a problem with that also.

Most vendors make diagnostic software for their laptops and I imagine Lenovo does so also. Try to run that and see if it finds anything. The problem of course is that running the diagnostic without the battery won't tell you anything about the battery and you can't run the diagnostic with the battery installed....

1 1/2 years is a pretty short life for a battery unless you were hard on it. Did the laptop get overheated? Did you run most of the time unplugged and then plug in occasionally just enough to recharge?

I would check out the external charger first and then try a replacement battery. It is best to get a genuine Lenovo battery (from the manufacturer, not Amazon or EBay). You might get lucky with a cheap replacement. If that doesn't fix it the problem is likely the motherboard charging circuitry.