DIY: Hardwire Radar Detector
Thread Starter
Super Member
Joined: Jan 2003
Posts: 675
Likes: 3
From: Dallas, TX
2018 GLS 550
DIY: Hardwire Radar Detector
So, here is a quick write up of my hardwire on my Passport 9500ix. I was able to take pics with my phone, but the battery was dying so some of them are kinda dark. It's fairly easy though.
First Step: Remove the Drivers Side Dash Panel. Behind this you will find the cables leading to the light switch. There is enough room to pull this out a bit so you can work with it. There is a pink/white wire, that's the one I used as it is ignition triggered. I tapped this wire with the hardwire kit that I have for my 9500.
For the ground I used the dash mounting bolts, this is a 13mm bolt head, you will need an extension, and be sure to pull the cable behind the dash panel as you can kind of see in the pic so it's not in the way.
Next, it's time to run the wire to where you mount the detector. Pull down the door seal, I ran the cable behind the seal, then where the A pillar meets the roof pillar I pulled the cable behind there and then across the top of the headliner to the mirror housing. From there, just run down the mirror/rain sensor housing, to your detector (I mounted mine center under the mirror)
The last step is to make sure it works, bundle up any excess cable, zip tie and tuck behind the light switch. close up the panel, and you are all set to go!!
First Step: Remove the Drivers Side Dash Panel. Behind this you will find the cables leading to the light switch. There is enough room to pull this out a bit so you can work with it. There is a pink/white wire, that's the one I used as it is ignition triggered. I tapped this wire with the hardwire kit that I have for my 9500.
For the ground I used the dash mounting bolts, this is a 13mm bolt head, you will need an extension, and be sure to pull the cable behind the dash panel as you can kind of see in the pic so it's not in the way.
Next, it's time to run the wire to where you mount the detector. Pull down the door seal, I ran the cable behind the seal, then where the A pillar meets the roof pillar I pulled the cable behind there and then across the top of the headliner to the mirror housing. From there, just run down the mirror/rain sensor housing, to your detector (I mounted mine center under the mirror)
The last step is to make sure it works, bundle up any excess cable, zip tie and tuck behind the light switch. close up the panel, and you are all set to go!!
Thread Starter
Super Member
Joined: Jan 2003
Posts: 675
Likes: 3
From: Dallas, TX
2018 GLS 550
I used the hardwire kit for the Escorts. You can get them from best buy for around $15-20.
They have the inline fuse and everything needed to do the hardwire included.
They have the inline fuse and everything needed to do the hardwire included.
Junior Member
Joined: Apr 2007
Posts: 20
Likes: 0
From: The OC
2015 C300 4Matic Sedan, 2015 C300W, 1997 Jaguar XK8,
Thanks for the writeup. Just curious but isn't there power available by the mirror housing. On other cars I've been able to grab power closer to the mirror where my detector was mounted.
Thread Starter
Super Member
Joined: Jan 2003
Posts: 675
Likes: 3
From: Dallas, TX
2018 GLS 550
I pulled the light console down, it's all enclosed and circuitry that I didn't feel like messing with, so that's why I went where I did. Also, the amount of extra cable I would have had to tuck in I didn't have room for up there. If you can find it, go for it though!
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Thread Starter
Super Member
Joined: Jan 2003
Posts: 675
Likes: 3
From: Dallas, TX
2018 GLS 550
That may be it, I apologize I did this all, then came back and wrote the post. I can double check but any of those wires should be a power wire of some form except the black/ground.
Thread Starter
Super Member
Joined: Jan 2003
Posts: 675
Likes: 3
From: Dallas, TX
2018 GLS 550
they do, but I'm not going to go out and buy another one just to have no cable. It took me all of 20 minutes to do this and I already had the hardwire kit from another car. Solo is a great detector though as well.
Junior Member
Joined: Jul 2011
Posts: 41
Likes: 0
From: Forest hills NY
2006 audi a4
I just got a beltronics 995 ($65, thanks radio shack!!!) and I want to do this hardwire on the c250. Ebay sells a bunch of hardwire kits w/o a fuse for $8. Is a fuse necessary when hardwiring a radar detector? Or should I get the OEM($20) smart cord with a fuse and remote mute button?
Junior Member
Joined: Jul 2011
Posts: 41
Likes: 0
From: Forest hills NY
2006 audi a4
Just did the hardwire this past wknd, thanks for your writeup johnny.
Did any of you guys who have done this have an issue with the wire tap? even after clamping on the wire tap, there was no exposed wire so I had to use a razor blade to cut out the excess rubber coating. Even with the exposed wire, I would have to wiggle it around in order for power to go to the RD. I just shoved in the excess hardwire cord in with the wiretap at an angle so that it will consistently get power. The wire tap was such a pain, I wish MB had the fuse box in the door panel, using a fuse tap would have been so much easier!
Did any of you guys who have done this have an issue with the wire tap? even after clamping on the wire tap, there was no exposed wire so I had to use a razor blade to cut out the excess rubber coating. Even with the exposed wire, I would have to wiggle it around in order for power to go to the RD. I just shoved in the excess hardwire cord in with the wiretap at an angle so that it will consistently get power. The wire tap was such a pain, I wish MB had the fuse box in the door panel, using a fuse tap would have been so much easier!
Newbie
Joined: Jun 2012
Posts: 3
Likes: 0
2012 C250
Hey everybody I am new to posting, but have been lurking for a while. Anyhow I was wondering if anyone figured out what the correct color to tap into was for a 2012 C250 sedan? I have a pink/red and a pink/grey. With the ignition in ACC mode, I have one wire that shows 5 V not 12. Could be my multimeter..lol
