It may not be relevant to your concern, but on Gen 1 volts, the daytime/nighttime sensor will sometimes switch the headlights on due low lighting conditions, or shadows from trees/buildings/clouds. when it does this, the displays switch to the physical setting of the display dimmer, which if it is all the way turned down, can be very dim, appearing to disappear in some cars. I've had this happen to me. something to check at least, try turning the dimmer up the next time this happens.