Abstract: A method includes receiving a first voltage from an intermediate node in a string of multiple light emitting diodes (LEDs). The method also includes receiving at least one second voltage based on a string voltage (VLED) across the string of LEDs. The method further includes identifying whether at least one of the LEDs has a fault using the first voltage and the at least one second voltage. The second voltage could be a single reference voltage, and a difference between the first voltage and the reference voltage could be compared to a threshold. Multiple second voltages could define a voltage range that includes a reference voltage, and a determination could be made whether the first voltage falls within the voltage range.

Abstract: A method includes receiving a first voltage from a first node associated with a first string of multiple light emitting diodes (LEDs). The method also includes receiving a second voltage from a second node associated with a second string of multiple LEDs. The method further includes identifying whether at least one of the LEDs has a fault using the first and second voltages. Identifying whether at least one of the LEDs has a fault could include comparing a difference between the first and second voltages to a threshold. Identifying whether at least one of the LEDs has a fault could also include determining whether a difference between the first and second voltages falls within a voltage range defined by higher and lower voltage limits.