How do you reprogram a transponder key for 01 galant?

To reprogram a transponder key for a 2001 Mitsubishi Galant, you'll need to have both the original key and the new key. Insert the original key into the ignition and turn it to the "On" position for about 10 seconds, then turn it back to the "Off" position. Remove the original key, insert the new key, and turn it to the "On" position within 10 seconds. The security light should turn off, indicating that the new key is successfully programmed. If you have trouble, consulting the vehicle’s manual or a professional locksmith may be necessary.