Method and device for testing at least one LED strip

A test device for at least one LED strip contains: a voltage source, by way of which a cold test voltage or a warm test voltage can be applied to a parallel circuit formed of a test resistor and the LED strip, and an evaluation unit which records the cold test current flowing when a cold test voltage is present and diagnoses an error if the cold test current deviates from a required value by an above-the-threshold amount. A test device contains a switching element connected in series with the test resistor and an error circuit connected to the at least one LED strip, which during the warm testing records an over-the-threshold deviation of a current flowing through the at least one LED strip from a pre-specified value and for an over-the-threshold deviation opens the switching element.