The following DIY works with any 8th Gen CIVIC that has a moonroof.
My wife loves her new Civic EX sedan but she really misses the homelink capability she had in her Pilot.
The Honda Autodimming mirror dealer option does NOT have Homelink capability (guess that would make too much sense). I purchased the Homelink autodimming mirror made by Gentex for LESS than the Honda kit (50-GENK40). Gentex seems to have an exclusive deal with the Johnson Controls folks. You can even get it with map lights an/or a compass/temp. You can also find these on E-Bay pulled from cars with new wire harnesses. Looks legit, but you never know......
Suggested site (no connection with said site. Just a happy customer):
www.autodimmingmirrors.com/dealerpricing
Tell them you are a RAV4world member (I know, blasphemy. But it saves you some bucks). Tell them this is an "Autoclub" purchase
You WILL need the foreign vehicle bracket and wire cover.
I wanted to do this install without messing with the A pillar (and the enclosed Air Bag). I figured there had to be the power needed in the maplight/moonroof controller. Use the existing Honda autodimming mirror instructions to remove the maplight/controller module. After the module is removed you will have two wire harnesses. One with a white connector and one with a green connector.
The light blue wire on the white connector is +12V Battery. The purple wire with the silver stripe on the green connector is +12V Accessory. Finding that was a real challenge. The accessory line stays high up to 10 minutes after the ignition is turned off or until the door opens.
The wire harness for the mirror:
White striped wire is +12V accessory
The middle wire is Grnd
The black wire is +12V Battery.
The attached picture shows the wires before soldering:
After soldering everything, tape everything up good with electrical tape. I used one of the mounting bolts on the map light for the ground.
Doug