No power to my aftermarket stereo 2000 accord
 

Today I tried installing a set of subwoofers in my 2000 accord ex, we learned early in the process that the stock head unit couldn't accept subs so we wired it all up and installed an aftermarket unit that my friend had lying around.
When we went to turn the car on and check if the unit was working it had no power. Couldn't turn it on, and now the cigarette lighter isn't working. I checked all the wiring and compared it to the diagram. As far as I could tell, everything seems to be correct. After attaching the speakers I was left with the white and green constant, the white and red ignition, the dimmer and illumination wires, a green/red one that I have no idea what it goes to, a small black wire with brown spots that I'm also unsure of, and a large black wire that I believe is the ground. I have the constant and ignition wires attached and I've tried both black wires for the ground, I still can't get any power to the stereo. It was just working this morning, but I can't go back to the stock unit now either because I had to cut off the harness to attach the new unit.
If someone who knows anything about this could just tell me what might be going on I'd seriously appreciate it. I've checked the 8 and 9 fuses and that's not the problem so I'm just not sure what to do now

Constant power should be white/green. The large black wire is ground. The solid red wire should be switched 12V.

The head unit needs both the constant and the switch voltage to operate. You may have blown a fuse by hooking up the small black/brown wire to ground.

There are schematics floating around the site somewhere.

I checked the #8 and #9 fuses and they were fine, any idea what those 2 wires are to? I couldn't even find them mentioned anywhere in the wiring diagrams I found

According to Haynes, the red/green and black/brown wires are for the front right speaker.

For the number 8 and 9 fuses, which interior fuse box are you checking? You should be checking the number 8 and 9 fuse in the passenger side interior fuse box. There is still the Accessory Power Socket relay in the circuit which looks to located on the backside of the passenger side fuse/relay box.

Honda wire color codes are wire insulation is one color or color with another color stripe. The second color is the stripe.

The GRN/RED is for the radio switch remote input (applicable to EX-V6). The GRN/RED wire runs from a cable reel sub-harness wire, which is connected to the remote on the steering wheel.

The small black wire with the brown dots should be consider a black wire. It is most likely the ground for the audio unit security input (applicable to EX model, which come with the factory security system) that runs to the passenger multiplex integrated control unit (MICU).

Thanks for the diagrams.

OP - in the future, buy the harness adapter and save your self a lot of work and hassle. cutting the harness should always be avoided.

use a multi-meter to check for voltage. measure DC voltage on the constant and ignition wires relative to the ground wire you are using. a proper ground is required.

how did you make your connections? solder and heat shrink? crimp connectors? a solid mechanical connection with proper insulation is required.

I had been checking the drivers side fuse box as I wasn't aware there even was a fuse box on the passengers side, in the future I will be buying the harness and attaching it that way, but for now I was just temporarily splicing the wires so I wasn't worried about it. I did blow the fuse on the passengers side and once I replaced it the stereo worked fine. Thanks everyone!