Glow Plug Indicator
WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
The glow plug indicator is located in the instrument panel cluster and informs the operator when the engine is ready to start. The indicator is controlled by the instrument panel cluster based on an electronic command signal from the PCM through the CAN. The on-time of the indicator is independent of the glow plug relay on time. As a prove out, the indicator is commanded on at every ignition switch cycle even though the glow plug system may not be operating.