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:
Shift Lock System Circuit
Troubleshooting
1. Connect the HDS to the DLC (A) located under the
driver's side of the dashboard.
2. Turn the ignition switch to ON (II). Make sure the HDS
communicates with the PCM. If it does not, go to the
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Malfunction Indicator Lamp
If the indicator comes on
while driving, it means one
of the engine’s emissions control
systems may have a problem. Even
though you may feel no difference in
your vehicle’s performance ...
Automatic Climate Control Sensors
The automatic climate control system is
equipped with a sunlight sensor and an
interior temperature sensor. Do not cover or
spill any liquid on them.
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