
Bring down the console and type
HelpUsObi 1
and press ENTER. This is the Quake III equivalent of sv_cheats 1, which doesn't work in Jedi Outcast. You can also type devmap <mapname> to load a specific map and have the cheats enabled once the map loads.
The cheat codes are essentially the same as Quake III: Arena. The main ones are:
You can give yourself force powers. You need to enable the cheats with HelpUsObi 1 and then use
These can all be set to 1, 2 or 3 representing Force levels 1, 2, 3.
If you do setForceAll 3, you'll get all powers at level 3.
If you do setForceGrip 2, you'll get grip level 2, etc.
For more cheats, see Cheat Happens.