I had just bought the AVIC D-3 from some dude off craigslist....Bunch of stuff was missing, the reverse extenstion wire was one of the things missing.

Is this just a regular wire??? Whats the in-line fuse resistor??? Can I just use regular wires???

I believe it's a resistor, not a fuse. You would have to find out what the resistor is rated at and pick one up at Radio Shack and wire it.

http://parts.pioneerelectronics.com/part.asp?productNum=CDE6825

Should actually be a diode shouldn't it, to prevent illumination of the reverse lights?

No, because the D3 isn't putting out power on that wire, it's looking for a signal coming in. The resistor is on there because it doesn't need the full amount of power running through the reverse light power wire to get that signal. Without it, it could possibly mess something up in the D3.

I have mine hooked up with out the risitor as I was getting any signal when I put the car in reverse. I cut the resistor off and connected without it and all worked fine.

Will it really mess up anything if I don't have it on ?

I'm not saying it won't... I mean, there's got to be a reason it's on there. They wouldn't have spent the money on putting it in if they didn't think there was a reason for it. But if it's working for you with no trouble, I guess you're fine.

I guess I will go with if it's not broke don't fix it. LOL .. Well see what happens.

I think it's a fuseable link. I am not sure though.