Those are some crazy prices! And I don't think that BMW oe either!
The way to find out if you have heated mirrors if you have two wire connections going to the mirror. And auto dimming feature is another connection, which is a plastic molding going around the mirror To another connection inside. And I have my new mirror installed. With just the heated function hooked up. (no dimming) I just left that connection unplugged. And no codes. Functions properly no problems.
And I have the winter cold weather package. But I think the e53 may have come with a standard feature of heated mirrors. It's is a German engineered BMW after all.

Heated, aspherical, light blue tint. New driver side mirror for e53. ($30 shipped in the US) pm me.

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2009 BMW E60 LCI 528Xi


SOLD
2002 BMW X5 3.0i E53