Cold Start Heater Relay (LPG)
WARNING: This page is about a different car, the 2002 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
Compuvalve signals cold start relay to operate cold start heater when compuvalve receives a signal from PCM through SCP Bus(+) or BUS(-) circuits that engine coolant temperature is less than 32°F (0°C).