Thinkpad 755C does not detect battery

[Guest]

Hello,

I have a ThinkPad 755C that will not detect the battery.

The laptop runs fine of AC power.

The Battery is charged to about 10.0 V.

When the battery pack is installed in the laptop there are no yellow or orange battery status indicators.

When I measuring the laptops charging voltage between DC/DC terminals 1 (+) and 4 (−), the voltage is about 13 Volts.
According to manual the charging circuit is working correctly if this is above 9.0 V.

Any ideas on what could be wrong.

Thanks
SN

[AlphaKilo470]

Could be an issue with the connector, it could also be an issue with one of the boards in the laptop or even the battery itself.