Ready Light Indicator (Hybrid)
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The ready light indicator informs the driver that the electric drivetrain is ready to operate. This indicator is required because the internal combustion engine is not operating all the time and the driver needs to receive the information that the vehicle is on. The input to the instrument cluster is a message from the PCM over the communication network.