Acura 3.5 RL Manual page 1155

Automatic Inside Dimming Mirror
Description ('02-04 Model USA)
The automatic dimming has a front-facing lux level sensor, a rear-facing lux level sensor, and a control unit. The control
unit receives signals from each sensor. Based on the difference between the two lux levels (the light outside the vehicle
and the light from the headlights of the other vehicle, etc.), the control unit controls the electro-chromic gel to reduce the
glare. This dimming function is canceled when the transmission is in reverse, or when the automatic inside dimming mir-
ror switch is turned OFF.
BACKWARD LUX
LEVEL SENSOR
SWITCH
FORWARD LUX
LEVEL SENSOR