501-09 Rear View Mirrors: Description And Operation (page 2 of 10)

INTERIOR MIRROR 

The interior mirror incorporates either manual dimming or auto-dimming. Manual dimming is performed with a lever on the 
underside of the mirror body. Auto-dimming is performed by electrochromic mirror glass. 
 
Depending on vehicle model and market, the auto-dimming interior mirror may also incorporate a HomeLink® universal 
transmitter. 
 
NOTE :  

 
Interior mirrors with the universal transmitter and/or the auto-dimming functions are connected to the vehicle wiring by an 
electrical connector concealed by the finishers covering the mounting stem. When the ignition switch is in position II, a 
battery power feed from the Central Junction Box (CJB) is supplied to the universal transmitter and/or auto-dimming 
circuits in the interior mirror. 
 
Light sensors on the front and rear of the interior mirror provide light level inputs for the auto-dimming function. 
 
Interior mirrors which incorporate the universal transmitter have buttons along the lower face for control of the universal 
transmitter and auto-dimming functions. They also have a dual colored status indicator on the rear of the mirror which 
illuminates when the auto-dimming and universal transmitter functions are active; green for auto-dimming and red for the 
universal transmitter. 
 

Auto-Dimming Interior Mirror with Universal Transmitter 

Auto-Dimming 

The auto-dimming interior mirror automatically dims to reduce glare from the headlights of following vehicles in dark or low 
light conditions. The auto-dimming function is only enabled while the ignition switch is in position II. 
 
On interior mirrors with a universal transmitter, the auto-dimming function can be selected on and off using the 

HomeLink is a registered trademark owned by Johnson Controls Inc. 

Item  Part Number 

Description 

1

 -

Universal transmitter channel 1 button

2

 -

Universal transmitter channel 2 button

3

 -

Status indicator

4

 -

Universal transmitter channel 3 button

5

 -

Rear light sensor

6

 -

Dimming on button

7

 -

Dimming off button

8

 -

Front light sensor