To Autoroute SMD components, the layer that those SMD components are on **must** be selected in:
Router Layers > **Configure Layers**
If that layer is not selected then the Autorouter cannot route a short segment of track from a single layer pad on the SMD component to a via to then transfer the routing onto any other layer.
Here is the schematic for a simple project with 5 through-hole in a circuit and 5 SMD resistors in the same way in a copy of the circuit.
![image.png](//image.easyeda.com/pullimage/6eWu31RO0RrhFe0ia0aT7wNrKHIighTilcqGEYTh.png)
And here is the PCB:
The SMD resistors are on the top layer.
The (Local) Autorouter is set to route on the bottom layer only:
![image.png](//image.easyeda.com/pullimage/Ca6gNxz7Ha70AASKjTw6hZa0x9c84wwZKw4ybG8b.png)
![image.png](//image.easyeda.com/pullimage/9eZl8xe3Ey1WVoOS21YoZnPKj0vP5zrqwZmNFQeD.png)
Only the 10 connections to the through hole pins are attempted and completed. No attempts have been made to route top layer 0603 SMD resistors on bottom layer.
![image.png](//image.easyeda.com/pullimage/H1pZzD5F7ebwQihu1eCALbHkB4JK2bO6FAaOCcKj.png)
Through hole resistors on top layer route on bottom layer only with no problems but no vias are placed to route top layer 0603 SMD resistors on bottom layer.