WARNING: This page is about a different car, the 2004 Subaru Outback, 2004 Subaru Legacy, and 2004 Subaru Baja. However, it is still accessible from the selected car via links, so may be relevant.
Connect battery and turn signal light bulb to the module, as shown in the figure. The module is properly functioning if it blinks when power is supplied to the circuit.
Fig 1: Connecting Battery & Turn Signal Light Bulb To Module