Lenovo ThinkPad 380ED ThinkPad 380, 385, 560, 560E, all 760, 765 and SelectADo - Page 548

Checking Operational Charging Note. Battery charging will not start until the Fuel-Gauge shows that less than 95% of the total power remains; with this condition the battery pack will charge to 100% of its capacity. This restriction protects the battery pack from being overcharged or from having a shortened life. To check operational charging, use a discharged battery pack or a battery pack that has less than 50% of the total power remaining when installed in the computer. Power on the computer while it is connected to the AC Adapter. If the battery status indicator does not turn on, power off the computer, remove the battery pack and let the battery pack return to room temperature. Reinstall the battery pack, and power on the computer (still connected to the AC Adapter). If the charge indicator still does not turn on, the battery pack should be replaced. Checking the Backup Battery (Nonrechargeable) 1. Power off the computer and unplug the AC Adapter from the computer. 2. Open the DIMM cover. 3. Remove the backup battery. (Refer to "1050 Backup Battery or DIMM" on page 574 to remove the battery.) 4. Measure the voltage of the backup battery connector. See the following figure: Wire Red Black Voltage (V dc) +2.5 to +3.7 Ground If the voltage is correct, replace the system board. 536 IBM Mobile Systems HMM