In some examples, a device includes a built-in self-test for detecting a fault between a first light emitting diode (LED) and a second LED. The device includes a first pair of pads configured to connect to the first LED and a second pair of pads configured to connect to the second LED. The built-in self-test is configured to control a first driver and a second driver to turn on, one-by-one, respective pass switches connected to the first and second pairs of pads. The built-in self-test is configured to then determine the first and second forward voltages across the first and second LEDs. The built-in self-test can determine whether the fault exists between the first and second LEDs based on the forward voltages.