Well, I didn't see a how to for this, so here we go. My reason to hard-wire was I always left my radar detector on when I got out of the car. I know this will slowly drain the battery, so I decided to fix it. I wanted to not ruin my Cobra's plug into the 12v so I had to purchase a 12v add on plug. They are $7 @ AutoZone This will not be needed for everyone's use of this How To.

Tools Needed:
Thin Towel
Flathead Screwdriver
Electrical Tape
12v Add a Plug(Optional)
Wire Stripper/Crimper
Any tool/pieces that you like to get wires to stay together once cut
Extra Wire(Again Optional)

12v Plug:


I understand from here on the instruction can differ if you choose a different location or have a different item to hardwire to your car's turning on but you'll get the just of it.

1. Place accessory in desired location

2. Using Towel and Flathead Remove any panels to hide the wire. Use electrical tape to hold the wire in place as needed. View my video here as for how mine was hidden:
Hardwire Accessory Cobalt SS - YouTube

THE MAIN PART:
3. Remove your trim around your deck(stereo receiver) and remove the left side or right side bottom panel that is just below your deck but nearest your gas foot. View video as above to see what I'm talking about. It's the panel that is removed and has a white plastic structure behind it and I point at the grounding bolt.

4. Create your ground wire as using location noted in video. It is the metal structure behind the panel removed that holds your whole dash/center console in place. It has a nut that is easily taken off and your can easy make this a ground point for your accessory.

5. (Mine is different kinda but it should be the same for you)
I had an aftermarket deck installed so bear with me, but there should be a Victory Red looking wire that ONLY gets power when your car is in the ON position, not acc. ONLY ON. This is the one your going to tap into. You may use a relay switch if you need more power that this wires 16ga(ish) supply and run a real power directly to your battery. Mine is powering a radar detector, so no worry. Before cutting the wire or anything too drastic, test that it only receives power what the key is ON(just before actually turning the motor over). It should be a ground when its not in the ON position.

6. As you can see my plug in the picture above it has a Red Wire and a White Wire. Red is to Power, White is to Ground. (IMPORTANT) You should have already hooked your white up to the ground I showed in the video and now you should have you Red/Power hooked up to the ON switch wire under your radio. Now you test. Plug in your Radar Detector or Accessory and make sure the item is ON. Now with the item on and the car off, it should not be on. When your turn your car on if should now turn on and stay on while the car is on. PERFECT. You've now made life easier by not having to fiddle with a 12v every-time you get in and out of your car.

If people are having issues finding this red wire that only turns on during Key ON. I can take a pic or make a video on how to access it and what it looks like. Shouldn't be hard to find hooked into your stock deck.

Thanks,
Bratboy90

Good Luck, video end of video to see my outcome

 

i bought an add a fuse and a hardwire kit and tapped into fuse 21 in the pass fuse box. no splicing whatsoever. my detector is also in the center of my dash so i only have a little bit of wire showing.
so easy my detector also goes on when i have it in accesory mode. works alot better than having to have to splice anything.





ground

a member on the other forum made a how to and thats what i used

 

Do you have a link to this?

 

There is no switched 12V going to the factory radio, it turns on via a data signal from the BCM when the key is turned on. Be careful of where you tap into a switched 12V source, you mess up the wrong circuit and your car could start doing weird things. Also stay away from any airbag system wiring... both the SDM and PPS have switched 12V wires going to them but should not be hacked into.

 

I think the reason you have a switched IGN power wire is because of the aftermarket headunit install, there isnt a red 12v switched wire from the factory.(or a red wire at all actually)

 

Nice how to and vid op, im just curious as to why your detector is on the passenger side of the car?? Just curious, lol

robk

 

Umm hmm. How to explain. Well first, I dislike placing in center or upper window. Bottom left it taken by boost guage, sooo...... Bottom right is best for me, has least elecrical interference also. During major group runs my passenger wears a headset. Im looking into making a place for a powered speaker of its own thats super loud. Because my car isnt exactly quiet at 120mph. Plus I play my stereo way too loud all the time.

Thanks for the comment

 

Direct Wire Fuse Kit - Radar Detector Accessories at Radar Busters