Volvo XC90 – Hardwire Valentine-1 Radar Detector

Vehicle: 2007 Volvo XC90 3.2.

This install was so simple that I declined to take photos (I was too busy to take photos). It really is quite simple, though. Make sure to have an 8-10ft analog phone cord with RJ-11 connectors. Not everyone does this, but I used the $13 install kit from Valentine Research. It has an inline fuse holder and red (+12V) as well as black (ground) cable with a receptacle for the device power cord. I also used a fuse tap and some basic electrical tools. Please read through the whole DIY before attempting.

DISCLAIMER: This is a demonstration of how I installed something on my vehicle. I assume no liability for you following this procedure on your vehicle. If you are unsure of how to proceed, please consult a service manual or bring your vehicle to a qualified technician.

  • Mount suction cups/device holder below rearview mirror
  • Tuck RJ-11/analog phone cord (power supply cable) up into headliner.
    • when traversing the dimming mirror/rain sensing wiper cable bundle, run the new cord between it and the windshield. If the radar detector ever falls, it will catch on this bundle instead of coming out of the headliner entirely.
  • Continue to tuck the cord down into the A-pillar between the cover and the windshield.
  • Open the driver’s door and stick a small screwdriver in the fusebox cover to pop it off. You should see a bunch of small fuses in a fusebox, staring you in the face. This is NOT where you will connect the radar detector, if you want the switched/ignition/12V setup.
  • Run the power cord/analog phone cord down into this area.
  • Crimp a circular ground connector on to the black wire coming from the install kit. Make sure it’s wide enough to go under the bolt that holds the fuse tray to the dash/body. There are two bolts lateral to the fusebox (so, near the door jamb) that are approx 8-10mm. Remove one of those and attach the black ground cable to it. This will be the ground for the circuit.
  • Shift your focus to under the driver’s side dash. Down where the light is, below the steering wheel. Take a Torx T25 bit and remove the two bolts underneath, then pop that panel out. Right next to that, where I want to say the “transmission tunnel” is (even though I know there isn’t a transmission in there), pop the fabric-covered piece off that runs from the accelerator pedal to the driver’s seat. Just pull it off. Now you can drop the panel that you removed the T25 screws from.
  • There is a fuse box down here. Why they hid it behind TORX bolts is beyond me. (This is why I only finger-tightened the torx bolts back in when I was done, in case I need to access this fuse box on the road!).
  • Now that you’re looking at the fuse box, find fuse #11. It’s for the switched 12V/cigar lighter. It turns on and off with the vehicle.  Pull that fuse. Insert a fuse tap. The inner fuse on the tap should be equivalent to the rating of the fuse for that socket. The outer fuse should be equivalent to the rating of the device that is being connected. For example, with fuse 11, the fuse is rated for 15A and should be placed on the inner part of the tap. The fuse for the V1 radar detector is rated at 10A and that should be placed at the outer part of the tap.
  • At this point, if all fuses are intact and the ground + power is hooked up as well as your radar detector, it should power on with a turn of the key and power off when removing the key. The reinstallation of panels/etc is the reverse of removal.