Core Issue
The %ONLINE-SP-6-DNLDFAIL:Module [dec], Proc [dec], Runtime image download failed because of [chars] error message indicates that the system is unable to download the runtime image to the indicated module and processor.
The first [dec] is the module number, and the second [dec] is the processor number. [chars] is the reason that the system was unable to download to runtime image.
Resolution
No action is required. The system recovers without user intervention.
If the error still happens contact Cisco Technical Assistance Center (TAC) before replacing the module.