The Schlage B and BD cylinder suffixes designate less small format interchangeable core (SFIC) cylinder prep for the lock. Any SFIC, 6-pin or 7-pin, can be inserted into th...
Check the following:
Debris in the cylinder
The cylinder cap could be too loose
Incorrect pinning of the cylinder
The cylinder plug is not returned to the neutral position with the cylinder s...
The "C" indicates small format IC core, which is the only core style Falcon products. The C987 will be provided less core unless -6, or -7 suffix is specified (6 or 7 pin core)
Example:...