The rumble pack only works with certain games I believe. I have tried mine, and it rumbles upon startup and rumbles during Metroid Prime Pinball.

The list of games are :

* Metroid Prime Hunters
* Magnetica
* Metroid Prime Pinball
* Star Fox Command
* Super Princess Peach
* Mario & Luigi: Partners in Time
* Clubhouse Games
* Shunkan Puzz Loop
* Legend of Spyro, The - A New Beginning
* Custom Robo Arena
* Star Trek - Tactical Assault
* Elite Beat Agents
* Mahjong Fight Club DS - Wi-Fi Taiou
* Power Pro Kun Pocket 9
* Puyo Puyo! 15th Anniversary
* Hotel Dusk - Room 215
* Picross DS
* Wish Room - Tenshi no Kioku
* Actionloop
* Diddy Kong Racing DS
* Wario - Master of Disguise

Taken from : http://en.wikipedia.org/wiki/Rumble_Pak

 

You use Rudolph's tool to enable the rumble, then start the game

 

I don't think Rudolph has added support for the Real to the 3in1 ExpPack Tool.

The 3-in-1 has to be set to rumble mode before a game can detect it as a rumble pack. You'll need the rumble patcher.

You can either patch the game you want to use rumble with (which can cause glitches or just not work), or you can patch some other small game, start that game to enable the rumble, then soft reset back to the Real and start the game you want to use the rumble with.