An intraocular lens injection device (10) comprises a tubular housing (15)with a plunger (32) longitudinallydis-posed within the tubular housing. An electric drive system (38)longitudinally translates the plunger so that its tip (25) engages aninsertion cartridge (20) to fold and displace an intraocular lens disposedwithin and to inject the folded lens into the lens capsuleof an eye. A control circuit (100) is configured to start translation of theplunger, responsive to user input, to detect at least onefault condition based on a counter-electromotive force produced by theelectric motor (42), and to stop translation of the plungerassembly responsive to the detected fault condition, which may compriseexcessive resistance to forward or rearward translation ofthe plunger or insufficient resistance to forward translation of the plunger.
