Spirit-X

Unlockable: Knife Reskin
Collect 50 unique dog tags on your soldier's account.

Attack Titan:
When the enemy Titan shields are down, attack it. The enemies will be waiting, but attacking the core will help you succeed faster. Always use teamwork.

Heal faster:
If you are playing as the Assault class, throw one medkit on the ground and hold one in your hands to heal twice as fast.

No intro:
Go into: "C:\Program Files\Electronic Arts\Battlefield 2142\mods\bf2142\Movies", and move all of the files out of the folder. you will now load to the login screen when you start the game.

Higher rank:
Note: This procedure involves editing a game file; create a backup copy of the file before proceeding. Use a text editor to edit the "profile.con" file in the "\battlefield 2142\profiles1CHEAT201" directory. It should be similar to this:

LocalProfile.setName "user"
LocalProfile.setGamespyNick "user"
LocalProfile.setEAOnlineMasterAccount "user"
LocalProfile.setEAOnlineSubAccount "user"
LocalProfile.setTotalPlayedTime 25467.3
LocalProfile.setNumTimesLoggedIn 9805
LocalProfile.setRank 0
LocalProfile.setCareerPoints 0
LocalProfile.setLastBaseUpdate 0

Replace the "localprofile.setrank 0" and "LocalProfile.setCareerpoints 0" values to:
LocalProfile.setRank 43
LocalProfile.setCareerpoints 54100

Dogtagger Dagger knife reskin:
Get 50 unique Dog Tags on your soldier's account to unlock the Dogtagger Dagger knife reskin.

Heal faster:
If you are playing as the Assault class, throw one medkit on the ground and hold one in your hands to heal twice as fast.