How do I check if my mirror is auto-dim
 

I am suspecting that it is not auto-dimming (I have a base model 2004 3.0i), at least it does not behave like an auto-dim in my 325i. So, how do I check? If it is auto-dimming and malfunctioning, what do I do about it? Any suggestions? Thanks!

Is there a little round "dot" in the middle at the top? If not standard mirror. Most likely in your case due to trim level.

No, only the red bump at the bottom. So looks like a standard mirror, huh? How much is it to replace with an auto-dimming unit? I got very fond of it in my car (X5 is wife's car).

I paid $295 6 years ago. You may find one on fleabay but make sure it fits you vehicle.

Thanks! Is it a DIY install?

So, If you get one with Auto dimming and compass, It is plug and play? how about side mirrors? do they come in auto dim as well?

You can change the mirror glasses to so called electrochrome glasses. I have mine from ebay - but check if cabling is there already.
Testing the dim function can be done with a bright flashlight pointing to the inside mirror.

Good luck

Is there any DYI instruction on replacing the regular mirror with auto-dim?

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