Km/h and MPH Indicator(s)
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.
km/h: The IPC illuminates the km/h indicator when the IPC detects that metric units have been requested. The IPC monitors the signal circuit of the ENG/MET switch. The IPC sends a class 2 message indicating the requested units to the head up display (HUD).
MPH: The IPC illuminates the MPH indicator when the IPC detects that English units have been requested. The IPC monitors the signal circuit of the ENG/MET switch. The IPC sends a class 2 message indicating the requested units to the head up display (HUD).