What can you do if the ground is not connected to the ground plane?
This can happen if you modify a circuit in EagleCAD and delete a segment of wire (net) in the schematic going to ground. The software can automatically rename the other end of the wire to a generic name. If you don’t notice this, then suddenly the wire (net) is no longer connected to ground.
Step 1: The Quick Ugly Solution
The quick, but ugly solution is to connect a jumper wire between the ground of your component to ground anywhere else on the board. Shown in the photo, we connected between the ground of the power in screw terminal and the ground test point.
Step 2: Getting Access to the Ground Plane
If you have a ground plane, then you should have access to ground close to your missing connection.
To open a path to the ground plane you have to remove a small part of the photoresist layer. This is the colored coating that protects the circuit board from oxidation and isolates the traces. Scratch off some of the coating around the ground of the screw terminal. Scratch off in two to three spots. Try not to scratch off the copper below the coating.
Step 3: Bridging the Gap
Solder in your component as usual. Add solder to the scratched off areas. Add more solder to bridge between the screw terminal and the copper ground plane.
You have now sucessfully connected your component to ground.