LED (Light Emitting Diode): General: Function
WARNING: This page is about a different car, the 2002 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.
The LED is supplied via +30 from fuse 25 (22a) and grounded via pin 27 on the TWICE control module. TWICE controls the grounding and hence activation of the LED and its flash frequency.