Lenovo ThinkPad 760CD ThinkPad 380, 385, 560, 560E, all 760, 765 and SelectADo - Page 437

Checking the Car-Battery Adapter 1. Unplug the Car-Battery Adapter cable from the computer. 2. Plug the Car-Battery Adapter into the cigarette lighter socket. Note: If the adapter is already plugged in, reseat it. 3. Measure the output voltage of the Car-Battery Adapter cable. See the following figure: Note: The Car-Battery Adapter does not charge the battery pack when the computer is powered on. This is not a failure of the Car-Battery. Pin Voltage (V dc) 1 +19.0 to +21.0 2 Ground If the voltage is correct, the Car-Battery Adapter is working correctly. Check that the computer runs with the AC Adapter. If it runs correctly with the AC Adapter, check the system board. If the problem still remains, replace the following FRUs one at a time. a. DC/DC card b. System board If the problem is not resolved when the system board is replaced, go to "Undetermined Problems" on page 447. If the voltage is outside the normal voltage range, do one of the following: - Try these test procedures in a different car, if one is available. - Replace the Car-Battery Adapter if the computer works correctly with the AC Adapter. Note: If the output voltage from the cigarette lighter socket of the car is less than 10.5 V dc, a continuous noise may be heard. The condition of the car battery should be checked by appropriate service personal. ThinkPad 765D (9546), 765L (9547) 425