A motor vehicle turn signal and a method for detecting an error in the turn signal are provided. The turn signal comprises a plurality of LEDs arranged in parallel banks and receiving current from a power source. A detector coupled to each of the parallel banks provides an error message if the current in one of the banks falls outside a predetermined limit. A current sink is coupled to the power source and is configured to be activated in response to the error message. When activated, the current sink causes a change in state of the power source. In accordance with one embodiment of the invention, detection of the change in state of the power source causes the generation of an error indicator to alert the driver to a turn signal malfunction.