Sounds like the receiver either needs re-programmed or a setting in your transmitter needs moved to another switch. I had a similar issue with a foamie plane I have a couple weeks ago. Went to go practice some maneuvers, and noticed after the receiver went through its little initiation cycle, my elevator wouldn't go to full throw for 3D rates. I've heard some of the 636 receivers come pre-programmed with the BNF models, and it cant be seen without plugging it into the computer to check the software / program internally. I fly with a DX8 G2 radio, moved my throttle cut from switch "A" over to switch "H" and the problem was solved - without having to use a computer. Just a quick change in the model setup on my radio (done at the field). Make sure though when you clear the switch it is cleared fully from its "responsibilities" on your radio / model setup. I believe it should go back to the inhibit (INH) option once everything is changed, but dont quote me on that - every model is different.
Another thought to add is, I believe there is a difference when you bind the airplane for just AS3X vs having AS3X and SAFE available. the process should be listed in the manual for your plane if you still have it. However, if not, I believe to have SAFE and AS3X you have to put your bind plug in, with your radio off, then connect the battery. Once the receiver starts flashing turn your radio on while holding the bind button down, and keep the radio away from the airplane about a foot or so until the bind process is complete. Just make sure before you start the process to have the right model selected on your radio. Because it will bind when the radio is turned on to whatever model is selected, and all of your settings on your transmitter should remain as they were originally too.
