A signal mirror system for a vehicle includes a reflective mirror element comprising a semitransparent nondichroic mirror reflector coated onto a light-transmitting substrate. The visible light transmission through the reflective mirror element is in the range of from about 1% visible light transmission to about 30% visible light transmission and the visible light reflectance is in the range from 40% visible light reflectance to 80% visible light reflectance for visible light incident upon the front side of the reflective mirror element. A turn signal display having at least one light emitting diode is disposed to the rear of the reflective mirror element and configured to emit light that light passes through the semitransparent mirror reflector to be viewed by a viewer viewing from the front of the reflective mirror element with a display luminance of at least about 30 foot lamberts.