Radar Detector Hard-wire installation

In this guide I'll show you how I installed my Valentine One radar detector in my 2022 Toyota Prius LE. Obviously the Prius isn't known to be a car for speeding around, but I already had the radar detector from owning it for years, and the one time i've gotten a speeding ticket was for going 6 mph over the speed limit, so even being aware of any police presence is beneficial for insuring you don't get hit for a few mph over the limit.

Installation Location

I always hardwire my wire harness in for the sake of having a reliable and clean installation. In the upper map light area, there is a Emergency Assistance Button that had a wire harness that supplied 12 volts when the car was on, and turned off when the car was off, which is how I like the power to run for my radar so I don't need to worry about turning it on and off everytime I get in and out.

Note: This will not disable or affect the function of the Emergency Assistance Button, the indicator LED should still be solid green if your service is active.

Hardware / Tools

  • Valentine One Radar Detector -
  • Mirror Mount - Purchase Link
  • Power Harness - Purchase Link
  • Wire Stripers / Crimper - Purchase Link
  • Vampire Wire Clips - Purchase Link

  • Note: If the mirror mount or harness are out of stock, you can probably find similar options on Amazon.

    Removing the Map Light Housing

    Start by using a plastic pry tool and inserting it on the bottom corners of the map light housing and prying out, you'll hear a snap sound as the plastic clips holding it in pop out.

    After you pop those out, there will be two clips in the top too, but you can just gently pull down the whole housing by wiggling it back and forth and it should pop out as well. (Make sure to check that the yellow clips aren't still in the roof when you pull this off, if they are just remove them and install them back into the map light housing)

    Once you have the housing fully removed, unplug the 3 harness's connected by simply unplugging them.

    Note: If you turn your car on while this is unplugged, You will hear it say over the speakers there's a connection problem with the safety system, you can ignore this as it won't happen again once the harness is re-connected.

    Installing the wire harness

    Grab the grey connector plug which connects to the emergency assistance button, and you'll be taping the green wire for constant 12v source when the car is on, and the brown wire for a ground connection.

    After you verify you have good connections by plugging into the radar detector and powering on the car, you should get constant power while the car is on, and no power when turned off. Route the power cable through the inside of the headliner and down into the mirror plastic housing.

    Reinstalling the the Map Light Housing

    Insure the wire harness is plugged in correctly and organized so the connectors will be sitting right on top of the plugs, this will leave just enough gap between the connectors and the roof and should clear without any resistance when you push it back into place.

    Mounting and Connecting the Radar

    After the map light housing is in place, install the radar mirror mount by clamping it around the mirror neck and tightening it down, slide your radar in and adjust it to your position of choice, and last but not least take your power cable and connect it, and your done! If you have excess wire you can push it back up into the roof for a nice clean finish.