I recently bought a used 97 civic. When I bought it, it already had an aftermarket stereo, however I'd like to put keyless entry into it, and I'd prefer the OEM system (which I understand goes through the factory stereo). So, if I buy a factory radio and remote FOB (cheap on eBay), and a wiring harness to supply power to the factory radio, is there any reason why this wouldn't work? Are there some radios that have keyless "built in" and others that don't, since some I see have big green connectors on the back and others have little green connectors? I've heard that some remotes only work with some radios, any ideas? I've also heard that you need a special code to activate the radio...any idea whether this goes for just using the radio for keyless entry, or whether the code is only needed for listening to music. Finally, I've heard that the dome light is connected through the radio as well, but my dome light works ok - you can turn it on or off, but it doesn't come on when the door is opened (no matter the setting). Any answers to any of these questions would be helpful, thanks.
Firstly, as far as I know, only the EX model of Civics of that generation
have factory keyless entry. (Possibly the Si as well? I don't know...) I
don't have much experience with this, but I would definitely try to get a
factory radio originally removed from car of the same model year and trim
that you are going to put it in.
Also, if you do not have the EX model of the 1997 Civic, I don't know if putting an EX factory radio in will give you keyless entry or not; there may be circuitry elsewhere in the car required to make it work. Another thing to consider might be the number of doors on your car versus the number of doors on the radio you want to put in; will there be a problem if the car is a coupe and the radio is from a sedan, or vice versa? Again, I don't know.
Secondly, the dome light itself will work without the connection through the radio -- the part that is wired through the radio is the door sensor for the dome light. So since your light doesn't turn on when the door opens, (assuming that the switch is set to "Door", of course) then probably either the factory radio has been completely removed or is not connected correctly.
Other issues... you'll need a reverse harness to connect the factory radio; Metra sells a Y-shaped harness which connects to the radio connector coming out of the dash, then to the aftermarket radio, then a few of the wires split from there to the factory one. (By the way, get Metra wiring harnesses if you need wiring harnesses... Scoche ones tend to be short) The factory radio is very difficult to fit behind the dash. This is what finally stopped me when I was trying to do this with my Civic; I finally gave up and had a shop do it, and it took them more than four hours, even with most of the wiring already in place from my previous attempts. There is a decent summary of what you need to do here: http://www.streetdreams.com/tech/honda/civic9698.html
BTW... my setup worked for about a week after the shop completed it; the keyless entry broke down one day and has not worked since. I'm still trying to figure out what to do with it. Sad story is here: http://www.car-forums.com/talk/showthread.php?t=10978
Hope that this helps...
I'm not sure if the car had factory keyless or not (since i'm not the original owner - according to http://www.handa-accessories.com/civic98.html all LX models have keyless entry built into the radio and that's reinforced when they state that "THERE IS NOTHING TO INSTALL IN THE VEHICLE". So from that, I've gathered that if the factory radio was still there, the only thing I'd need is the remote. I guess I don't know if that implies that the "Radio" has the keyless entry system, but not the rest of the car, or what. It does seem weird that Honda would put the keyless entry system into every car and then not sell it for some (saving themselves only the cost of the remotes). But then again, my car does have the fully wired green harness which apparently is what is needed for keyless entry. What do you think?