06 Lincoln LS won't start

Car wouldn’t start on Wednesday so wife had neighbor jump start the car and she took it to the auto store and had the original battery replaced. On Friday, while driving the car, the battery light came on so she took it to the auto store to have the battery checked. When they went out to check it the car wouldn’t start, only click. The battery has a full charge and doesn’t drop when the key is turned. I pulled the starter and had it checked…it’s good. I’ve checked relays and fuses and am coming up with nothing. Any ideas?

Start with the cables and connections. Make sure the cables are good and ALL the connections are free from corrosion etc.