Hardwire Radar in 20 Minutes for $20

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Apr 10, 2019 | 08:27 PM
  #1  
I have always paid a shop to hardwire my radar detectors, but decided to do it myself this time.

I found an old post from killer75 where he mentioned using the brown and red wire in the electrical connector behind the rear view mirror. Trying to take the housing behind the mirror apart proved more difficult than I thought, so I asked a friend who is mechanically more inclined to help. Using a trim removal tool, he took the left side housing apart and the rest was easy. The key is knowing where the 3 locking tabs are located.

Here are the steps I used:

1 - First push down on the tab close to the top of the left side housing, once that is lose, push down on the 2 tabs that are close to each other at the lower part of the housing.




2 - Using
this wire harness this wire harness
on Amazon or similar harness with RJ11 connection, pass the wire harness through the vents in the left housing.


3 - Run the wire through the plastic “U-Shape” loop that is close to the electrical connector and tie wrap it, so in case your suction cup gives in a hot day, it doesn’t yank the wire out. Using the small pins of the wire harness, insert the black wire into the brown wire on the 3-pin connector and red wire to the red wire. It is easier if you take the 3-wire connector out, insert the pins and reconnect the 3-wire connector back.




4 - Snap the left side housing back in. That is it, you are done! The radar comes on when you open the door and will go off on the final hibernation mode.


Reply 7
Apr 11, 2019 | 07:14 AM
  #2  
Super helpful write-up! Thanks for posting this. I couldn't figure out how to get that cover off without breaking it, when I was wiring my dashcams, so I gave up eventually. Looks like it's time to revisit that darn thing.

I wish we could use blendmounts, but I think for radar I'm going to have to go the sun visor route, as I hate suction cup mounts with a passion. But it will still be very useful to be able to wire it in under the mirror.
Reply 0
Apr 17, 2019 | 04:23 PM
  #3  
I don't see how u reached that top tab it seems like the rear view mirror is in the way. Unless I'm looking at it wrong.


Quote: I have always paid a shop to hardwire my radar detectors, but decided to do it myself this time.

I found an old post from killer75 where he mentioned using the brown and red wire in the electrical connector behind the rear view mirror. Trying to take the housing behind the mirror apart proved more difficult than I thought, so I asked a friend who is mechanically more inclined to help. Using a trim removal tool, he took the left side housing apart and the rest was easy. The key is knowing where the 3 locking tabs are located.

Here are the steps I used:

1 - First push down on the tab close to the top of the left side housing, once that is lose, push down on the 2 tabs that are close to each other at the lower part of the housing.




2 - Using this wire harness on Amazon or similar harness with RJ11 connection, pass the wire harness through the vents in the left housing.

3 - Run the wire through the plastic “U-Shape” loop that is close to the electrical connector and tie wrap it, so in case your suction cup gives in a hot day, it doesn’t yank the wire out. Using the small pins of the wire harness, insert the black wire into the brown wire on the 3-pin connector and red wire to the red wire. It is easier if you take the 3-wire connector out, insert the pins and reconnect the 3-wire connector back.




4 - Snap the left side housing back in. That is it, you are done! The radar comes on when you open the door and will go off on the final hibernation mode.

Reply 0
Apr 17, 2019 | 09:09 PM
  #4  
Quote: I don't see how u reached that top tab it seems like the rear view mirror is in the way. Unless I'm looking at it wrong.
You will have to play and move the mirror to get it to the best position for reaching the top tab and use a trim removal kit like this
https://www.amazon.com/gp/product/B07HRNKY8P/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 https://www.amazon.com/gp/product/B07HRNKY8P/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
or similar tool to put pressure on the top tab. It takes a little finesse. Snapping it back is a lot easier.
Reply 1
Apr 18, 2019 | 08:50 AM
  #5  
Great write-up!
I initially tried to place our Max360c in the same position but somehow could not get it to be level due to the curvature of the glass.

Installed it above the dash instead and wired into the passenger footwell.
Reply 0
Apr 24, 2019 | 12:44 AM
  #6  
Thank you.
Just wired mine up that way with the exact same harness from amazon. Removing the trim piece was not too hard. Very nervous i’d Break a clip using just a flat screwdriver but it popped right off. The challenge was getting the hot wire in. It just didn’t want to squeeze in there. Finally got it about half way and hoping it will stay.
My ziptie broke but I think there is enough tension on the wire through the vents in the trim it will hold it if the mount drops.

I codnt quite get the two trim pieces flush but you can’t really tell so left it as is rather than push it.

Thank god that ugly wire dropping down to the dash is gone
thanks for the great suggestion.
Reply 0
May 3, 2019 | 08:11 PM
  #7  
Major thank you to N-4Speed for starting this thread. I have been debating hardwire options for some time, Many have posted their versions in past, in my opinion this is the way to do it.
Trim tools and the helpful link for the wiring that was posted above is all you need.
Thanks to this thread, I just spent a few minutes to do this, and it looks great, works as it should, and is SUPER clean.

Thank you again @ N-4Speed for sharing!




Reply 1
May 23, 2021 | 04:07 PM
  #8  
great thread, thanks for sharing the detailed pictures of the location of the tabs and the colors of the wire. I just finished hardwiring my radar detector ( Max360c) into my 18' GTR. I also wanted to share some pictures of a homemade radar detector holder. I used a L-bracket from Home depot and bent it, to position my detector next to my mirror and close to the headliner. I attached the detector to the screw hole of sunvisor (I used a slightly longer screw from HD with the same thread size and a neoprene washer to keep it from rubbing). I used the velcro, (the kind to hang picture frames) that feel more like short pegs on each side that click together rather than the traditional hook and loop. It holds it very securely and have had it in place for almost two years without a single drop ( the suction cup used to fall off all the time due to hot weather and i had to mount it under the mirror). The only down side is that the visor can click into the holder but to bring it down for the sun it will hit the radar detector (bc the max360 is really long), so unclip the visor and then bring it down. I finally hardwired the power this weekend. Hope it helps anyone interested in this.





Reply 1

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Feb 17, 2023 | 10:25 PM
  #9  
Worked Like A Charm
The cord mentioned was not available, but there are a lot of them on Amazon. Get the one with the narrowest blades. You may have to buy an assortment of 3 like I did.

Pretty much took 20 minutes. I used a trim too to split the housing right above the mirror swivel like he said and then split the second area behind it.

Don't forget to feed the cord through the housing piece grill first, and then through the loop with the zip tie, and then plug it in. I did not try to remove the plug because I could see straight up into the plug by kind of laying backwards over the console and looking up at it from directly below, sitting in the driver's seat with my legs out of the car.

My install was a new Valentine One Gen 2.
Reply 0
Dec 10, 2024 | 12:21 PM
  #10  
Nice clean mount!! You should mass produce and sell them! I will be the first one buying one.
Reply 0
Mar 5, 2025 | 02:56 PM
  #11  
Awesome post. I just did mine (Escort Max 360c MKII) on my 2016 E350 4Matic Sedan using this cord:
Amazon Amazon
. The Escort Drive Smarter app replaces the need for a SmartCord.
Question: any assistance on hardwiring a dashcam on this vehicle? It does not have a fuse box in the dashboard, only engine and trunk. I saw in one of the above posts by Wolfman that he wired his detector into the passenger footwell. Is it possible to do that with a dashcam, and if so, what wires to tap into? I have a TypeS dual view 4k dashcam with the hardwire kit. Any assistance would be appreciated. Thanks again for this great thread.
Reply 0
Mar 21, 2026 | 08:37 PM
  #12  
Just did mine. Does anyone else radar stay one a few minutes after shutoff? Will it be an issue later on with power drain?
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