I've posted this to a couple of honda forums but I thought I'd try a couple of electronics forums too. Thanks for any help.
I undertook my project of adding a map light assembly into the
>headliner of my 98 civic LS today. I had to remove all the upper
>interior trim to pull down the head liner, but it wasn't too bad. I
>mounted the map light assembly and have put everything back together.
>I haven't figured out the wiring, maybe someone here can help.
>
>My Civic LS 4D is a '98, the dome light has two wires only. One leads
>to the battery + , the other comes from the door switches. (I have the
>'98 wiring diagram) The grounding comes from being screwed to the
>metal frame of the roof.
>
>The map light is from a 2001 Civic EX 2dr. There are 4 wires (see
>picture)
>
>
>
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>
>From looking at it, I'm thinking black is ground, red is (+), but
>there is still blue and green. Green is possibly for the door switch
>lead, but what about blue which is tied into yellow (thus tied to
>white)?
>
>I have to make four wires become three. I'm either going to have to
>tie two or leave one out. Anyone have any clearer idea of this than I
>do?
As a follow-up, I decided that blue and red were both (+) so tied them together to the (+) lead. Black was ground, green was door switches. I wired it up this way and the map lights work, the original dome works, but the new dome blows the fuse when I turn it on. The new dome is what's related to the blue wire (if you look at the picture it should be clear) So evidently I can't just tie it to the red, although if I exclude it there is no (+) lead to the new dome light. Can anyone figure out how I might wire this differently? Thanks.