Lenovo ThinkPad 760CD ThinkPad 380, 385, 560, 560E, all 760, 765 and SelectADo - Page 144

If the power-on indicator does not turn on, check the power cord of the AC Adapter for correct continuity and installation. If the operational charge does not work, go to "Checking Operational Charging." 1. Unplug the AC Adapter cable from the computer and measure the output voltage at the plug of the AC Adapter cable. See the following figure. (16 - 10 V) Pin Voltage (V dc) 1 +14.5 to +17.0 2 Ground Replace the DC/DC card. Replace the system board. If the problem is not corrected, go to "Undetermined Problems" on page 149. If the voltage is not correct, go to the next step. 2. Unplug the AC Adapter cable from the ac power outlet and wait 5 minutes or longer to allow the over-voltage protection circuit to be fully discharged and initialized. 3. Plug the AC Adapter cable into the ac power outlet. 4. Measure the output voltage of the AC Adapter. 5. If the voltage is still not correct, replace the AC Adapter. Note: An audible noise from the AC Adapter does not always indicate a defect. Checking Operational Charging: 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. Perform operational charging. If the battery status indicator does not turn on, remove the battery pack and let it return to room temperature. Reinstall the battery pack. If the charge indicator still does not turn on, replace the battery pack. If the charge indicator still does not turn on, replace the DC/DC card. Then reinstall the battery pack. If the reinstalled battery pack is not charged, go to the next section. 132 IBM Mobile Systems HMM