How To Reprogram a Key Fob Step 1: Replace the Key Fob Batteries. ... Step 2: Enter Your Target Car. ... Step 3: Turn on The Ignition. ... Step 4: Press the Remote Lock Button Key. ... Step 5: Listen for a Locking Sound. ... Step 6: (OPTIONAL) Programming More Remotes. ... Step 7: Turn off the Ignition. ... Step 8: Test Your Fob (s) Outside Your Vehicle.