noise from rear when locking car

[bynon1]

there's a noise coming from the rear offside when i operate the central locking but only to close sounds like a motor or relay running but it only just started today
car locks fine but something isn't right by the sounds of it
has anyone any ideas or suggestion of what the problem could be?

 

[jedred1]

Check the gas flap locker mechanism. Open the gas cap flap door then try to lock/unlock while watching the locking solenoid