Weiser door handles, manufactured by a division of Black & Decker, are all supplied with a lifetime free replacement warranty on mechanical failure. Provided the lock was installed and maintained according to the instructions that came with the lock, the extent of repairs will consist in removing the lock and sending it to Weiser for a replacement. One major issue that is not covered under this warranty is a lock being "blown" or made unusable due to inserting a key other than the correct Smart Key into the key slot. In these cases the owner will be responsible for the repair, which consists of resetting the key cylinder.
Use a screwdriver to remove the mounting screws in the faceplate of the interior base ring around the handle or knob. Pull the exterior half of the handle from the door with the lock cylinder inside. Set the interior knob or handle aside for reuse.
Insert the narrow tip of the cylinder lock removal tool, available from Weiser, into the end of the long cylindrical shaft protruding from the center of the handle mechanism. Twist counterclockwise until the rectangle at the spindle's base aligns with the rectangular notch in the plate at the base of the spindle.
Locate the metal release tab underneath the plate at the base of the spindle. Use the tip of the tool to press down on the tab while pulling away from the handle on the spindle to separate the spindle from the handle to reveal the cylinder release. Insert the fork end of the tool into the rectangular slot in the plate you removed the spindle from. Push firmly to eject the cylinder from the handle face.
Rotate the bottom dial of the cradle to the right until it stops. Insert the lock cylinder into the cradle from the top, aligning the rectangle tab with the slot in the cradle's top opening. Rotate the bottom dial a half turn to the left, until it stops with the arrows aligned on the face.
Insert the SmartKey tool into the hole beside the key slot on the lock cylinder face. Press the tool until it slides all the way in, then pull it back out. Insert the SmartKey you want your lock to "learn." Do not rotate the cradle or lock cylinder. Pull the key out gently to slide the cylinder out of the cradle, with the key still inside.
Hold the lock cylinder and turn the key clockwise 90 degrees. Remove the key. Reinsert the lock cylinder into the handle, pressing it firmly all the way in. Press the spindle back into the inside face of the handle. Twist the spindle clockwise to fasten it in place.
Replace the knob halves through the handle's striker assembly and align the halves so that they slide together. Thread the two mounting screws back into their holes in the interior handle base plate and tighten with a screwdriver.