When the power input plug was jiggled, the green charging light
would go on and off. Finally, it got so bad that you had to hold the
cable in just the right place to make the battery charge.
Straight forward. Been inside the G4 before so no issues at all. Took about 1.5hr since I left the hard drive bracket out upon reassembly.
Looked over the old charger board. The problem was obvious. One solder connection for the connector shell had broken. The other side of the shell was still soldered but the mechanical stress on the center pin was too much. This was especially true since only one side of the center pin had been soldered. The center pin was thus sliding back and forth making and breaking the connection to the printed circuit board. The board was slightly blackened where the pin was making the intermittent connection. Had I known earlier, this was have been repairable with touching up two solder joints.
Use an ice cube tray to put the screws in and label the screws as to where they came from.