Q: My 2005 MBZ SL500's dimming rear view mirror stays dark in daylight unless I turn on the adjacent overhead light.

asked by on November 01, 2017

My 2005 MBZ SL500's auto-dimming rear view mirror stays dim (dark) in daylight unless I turn on the adjacent overhead light. With the light on somehow the mirror knows to go to daylight mode. The dim is fine at night and doesn't go to daylight mode. Is there an easy fix to this?

J. Curtis jcurtis595@gmail.com

My car has 52000 miles.
My car has an automatic transmission.

Electrical components are not working Inspection $79.99 - $99.99 Get a Quote

What you are describing is likely a consequence of a failure of the ambient light sensor on the forward facing part of the mirror, although check to be sure that the light sensor is not somehow "blocked". The sensor is usually integral to the mirror assembly and so the mirror assembly would have to be replaced in that event. Hypertechnically, the sensor could be replaced by an electronics technician, who is skilled at board level work, and that might be an option for you if Mercedes Benz either charges an exorbitant amount for a new assembly or the new assembly is no longer vended. If you would like a certified mechanic to diagnose this issue and get a repair, or replacement, implemented (btw, used copies of the mirror are available, if MB does not vend the part), please request an electrical components diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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