* The `Connect Pad to Pad` tool will *not* draw ratlines between isolated pads or vias that are not part of a component PCB footprint. * The `Connect Pad to Pad` tool in the `PCB Tools` palette is to draw ratlines between the pads of PCB footprints, even if the footprints are on different sides of the PCB. This tool is used to build a netlist of the connectivity of a PCB that is being created without a schematic. (However, please see: https://easyeda.com/forum/topic/The_best_way_to_design_a_PCB_in_EasyEDA-ThR3pwqIC for an explanation of why it is much better to create a schematic first and then convert that to a PCB.) If you place some PCB footprints on a new PCB and then use the `Connect Pad to Pad` tool, you will find that EasyEDA draws the ratlines. The `Connect Pad to Pad` tool does not work just connecting isolated pads or vias, because they are physical elements of the routing between the pads on components and so are layout dependent. For example if there are two SMD footprints both on the same side of the board then no vias would be needed to connect the pads but if the two components are on opposite sides of the board then vias would be needed to complete the routing between the component pads. This means that the isolated pads or vias are not directly part of the connectivity between a pair of component pads and so are not something you can draw a ratline to or from. If you need to place a single pad somewhere then you can use a single pin through hole PCB footprint such as HDR1X1 (from the EasyEDA Libs) or a surface mount single pad PCB footprint such as Test_Point from the SHIFT+F searchable library. Once the basic PCB design has been connected up using the `Connect Pad to Pad` tool then routing (tracking) can be started with any vias needed to change layers placed as required as routing progresses.