I sold my Volt today, and the buyer did not want the radar detector nor the dashcam, so I ripped them out and will look at putting them in the Polestar 2 when I get it. The dashcam is a DOD RX8W
https://www.amazon.com/DOD-TECH-RX8W-Rearview-Mirror/dp/B00V8LF0E6 (now 3 years old or so). It has micro-USB at camera end and 12V cigar male at the power end, so I will look at installing a cigar female off the fuse box under the glove compartment. I like it well enough but am going to look into one of the newer styles that also has a rear camera if I can see a good way to fish the wire through the PS2. (Duct-taping it to the glass roof is not an option.)
The Valentine One radar detector (mine is Gen 1) offers a number of power arrangements; you can see their black dual RJ11 (telephone) style gizmo in the first picture. It has a red lead that passes through an inline fuse (1A; the black thing in the middle of the red wire run) to a M blade connector (the out-of-focus pale blue thing above my thumb; I can't remember if they provided that or if I added it to their red lead), and a black ground lead to a spade connector. I found a convenient hole in a metal part under the dash and put a bolt, washer, and nut through that to attach the ground.
Then, I added the micro fuse tap (as shown by the Professor above), with a 5A fuse installed for my circuit (of course, the 1A would blow first if there was an issue). This clipped into a spare fuse receptacle so was not shared with any car circuits, thus no need for the lower fuse to be occupied; I verified that fuse was powered on-off by the car starting or shutting off ("ignition switch" is going to be passé REAL SOON NOW). Instead of using the crimp connector that comes on the fuse tap, I crimped on a piercing style adapter (the blue thing by my thumb tip in second pic, which may have come from Valentine as the other end of their system); this has the female connector for the red lead's M to plug into.
I put some sticky tape backed velcro on the back of the RJ11 gizmo and stuck it near the fuse box out of sight.
Finally, one runs the phone cable from the RJ11 connector up to the radar detector through the door seals and roof liner. I like the MirrorMount brand
Mirror Mount Device Brackets – RadarMount.com - The Radar Detector Expert ™ attachment to hang the radar detector from the car mirror's post. I will have to see if it fits on the PS2 post.
Both devices have worked fine for the last 3-4 years in the Volt, so I can't imagine why they won't work in the PS2, barring any weirdness with PS2 radar emitters...
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