Official Honda Alarm Problem

I'm switching out the head unit in my wife's 99 civic Si, and can't get power. There is an official Honda alarm on the car, would that cut power to the head unit if the wiring harness was disconnected? I checked the head unit in my CR-V and it works fine. I also switched the old radio back into the Si and it doesn't have power either.

If it is the alarm, how do I convince the alarm that everything is ok? It can't be a code on the radio, the radio I am taking out is also aftermarket. The original honda radio hasn't been in the car for three years. I just can't figure out what I need to do.

Thanks for your help

I don't think that your alarm (factory or otherwise) would have anything to do with you head unit not getting power. What I would look for is a blown fuse, particularly the "back-up" fuse under the hood. It may also be labeled as something else in the newer civics but there is a fuse under the hood that provides the memory power to the radio. The radio has two power sources, one that is constant and one that is on when the key is in the accy and on positions. The radio will not operate without both of these wires powered up. If the fuse is fine, I would check the harness itself, it is possible the not have pins aligned properly when you plug the harness in. They can also be pushed out of the adapter harness when you plug them in. Just a few things to check.

peace
Griff