5700 is a ASF cam error most likely. Here the Canon proceedure for fixing it!
DESCRIPTION: 5 Alternating Blinks (SFP) / ##356 (MFP) - ASF Cam Sensor Error
SOLUTION(S): Adjust the Screws & Main Case Unit
Movement (i.e. from shipping) may cause the plastic guide to move away from the chassis. When this
occurs, the gears cannot rotate properly causing a grinding noise and 5 alternating blinks (SFP) or ##356(MFP) - ASF Cam Sensor Error.
Procedures
Step 1: Remove the Left and Right Covers and the Main Case Unit (main cover).
Step 2: Remove the 4 mounting screws from the Chassis.
Step 3: Remove the Main Unit from the Bottom Case.
Step 4: Turn the Main Unit over (upside down) and place on work surface.
Step 5: Inspect the ASF section of the Main Unit for a gap between the white plastic
guide and the Chassis.
Note: The size of the gap varies. Even if the gap is not visible,
complete the steps below.
Step 6: Disconnect the appropriate cables and remove the Logic Board from the
Chassis.
Step 7: Loosen (do not remove) the 4 mounting screws (the mounting screws can be
found behind the logic board) on the Chassis.
Step 8: Re-seat the white plastic guide so it sits flush against the Chassis. The
tip of the white plastic guide should sit slightly inside the
Mounting screw hole. When seated correctly, the gap will no longer be
resent.
Step 9: Tighten the 4 mounting screws without causing the plastic guide to shift.
Step 10: Reassemble the printer and retest.