Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to troubleshoot common problems with a gps navigation unit [title] The gps navigation unit doesn't start up/could not open the gps navigation unit. [substeps] The key is not turned to acc or ignition position. Turn the vehicle key to acc or ignition position.

Ending1: The power cable has not been connected to the gps navigation unit. Connect the power cable to the gps navigation unit. Ending2: The key is located on the top of the unit and the unit will start on if you turn it. Click on " running " on the display on the dashboard. Ending3: Turn the gear knob with your hands to the right to gain access to fuel pump. Press shift at the button on the bottom of the unit. Ending4: [title] Once the unit has stopped running, press the car into gear and turn on ac running system. [substeps] If the unit does not start the process will not be successful.

Answer format: ending1/ending2/ending3/ending4