I didn't use the code method. Since I always copy from the OEM remotes anyway. Here are the procedures:

On the 921 remote, go to menu/installation/diagnostic/teach remote/confirm yes.
You can then aim the learning remote at the 921 eyes located at the lower right hand corner of the unit (approx 12" away). Then go through the normal learning method. The 921 will flash the signal into your learning remote as you press buttons on the 921 remote.

To exit, press any button on the front panel of the sat box. You should be in business then