Honda Accord: System Description
EX-L, EX-L PZEV models
The automatic dimming Inside mirror has a front-facing lux level sensor (A), rear-facing lux level sensors (B), 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 glare. This dimming function is canceled when the transmission is in reverse, or when the automatic dimming off button (C) Is turned OFF.

Circuit Diagram
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Test/Replacement
EX-L, EX-L PZEV models
1. Remove the cover (A), then disconnect BP connector
(B).
2. Turn the ignition switch to ON (II).
3. Measure the voltage between terminal No. 2 and
body ground.
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See also:
Circuit Diagram
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Outside Air Temperature Sensor Test
1 Remove the outside air temperature sensor (see page
22-353).
2. Dip the sensor in ice water, and measure the
resistance. Then pour warm water on the sensor, and
check for a change in resistanc ...