Open LED detection and recovery system for LED lighting system

A fault-tolerant controller (205) for a lighting system (200) comprising a plurality of light emitting diode "LED" circuits (201-1, 201-N) and a controllable power source (203) providing a drive voltage (204) to power the plurality of LED circuits (201-1, 201-N); the controller (205) comprising: a minimum voltage selector (210) adapted to determine a minimum voltage (211) from a plurality of feedback voltages (202-1, 202-N), one feedback voltage (202-1, 202-N) for each of the plurality of LED circuits (201-1, 201-N); a control unit (209, 213) configured to cause regulation of the drive voltage (204) based on the determination of the minimum feedback voltage (211); an overvoltage warning mechanism (230) configured to determine an overvoltage warning condition (231) based on the drive voltage (204) exceeding an overvoltage warning threshold (292); wherein said controller (205) is configured to identify one or more open-circuit conditions, one for each LED circuit (201-1, 201-N) for which the respective feedback voltage (202-1, 202-N) is below an open-circuit threshold (293), and cause said minimum voltage selector (210) to exclude the one or more respective feedback voltages (202-1, 202-N) associated with LED circuits (201-1, 201-N) associated with open-circuit conditions from said determination of said minimum voltage (211).