LH Turn Signal and RH Turn Signal Indicator Inputs
WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
The left and right turn indicators are driven by hardware inputs from the exterior lighting system. The signal is active high (12 volts) and inactive when circuit is open. During hazard mode, both the right and left turn signal circuits are active high, causing both the right and left turn signal indicators to illuminate at the same time.