Has anyone here installed a dashcam that is powered by USB from the rearview mirror + headlight dimmer/rain detector, & etc. that is buried in the enclosure.
I'm not interested in running a power cable from a fuse box, under the upholstery, and under the headliner to power a forward viewing and a rear viewing camera. BTDT in another car.
I'd like some info on that, but also, recommendations for types and brands with ease of installation.

Thanks.

Randy

 

Well its easy enough to try. by using an USB splitter and post how that works out for you.
Saving an extra 15-20 minutes of easy work to do something in a correct and conventional way or what reading the manufactures instruction for installation correctly or at least recommended is often not a DIY methodology.

I prefer and use several Rexing dash cameras in 3 of my vehicles . I have tried other brands but tend to like Rexing.
I have 2 in each of 2 of my vehcle and one I have 3 .
I took that 15-20 and easy ran the cable out of sight on both front and rear window instalations,.On all my from camera I also have the GPS

Rexing dash cam videos from my Mazda

Mazda and your dash cam shorts - Mazda Forum - Mazda Enthusiast Forums

 

I forgot to mention using an existing OEM power supply as in tapping into an existing components power connector as an example a power mirror without installing one of these for your accessories can void a auto manufactures Warranty on the system having an electrical or other related to that system problem(s). Plus adding a separate fuse rated one step lower than the main tapped circuit (if meets the added products installation of power supply rating) protect both your Mazda's electrical system and the added electronic device.

 

I’ve seen setups like that done, and it’s definitely possible to use the power that’s already behind the mirror instead of running a long fuse‑box tap under the dash, as long as the feed you’re tapping can actually supply enough current for a camera. The key is to confirm whether the USB or harness in your mirror housing is just a data/low‑power line or a true switched 5 V/12 V power source — many OEM mirror USB feeds aren’t designed to run a dashcam and will reset or fail if overloaded. If you can identify a switched power line in the mirror harness or an accessory lead near the headliner, you can splice a small USB adapter there and run your forward and rear camera cables neatly along the headliner and A‑pillars without a big cable drop to the fuse box. As for brands, compact units from BlackVue, Thinkware, and Vantrue tend to be easiest to install in these kinds of setups because they’re designed for low‑profile wiring and have clean, low‑current power options, which makes hiding and routing behind trim much simpler than bulkier units that need constant 12 V taps.

 

keep in mind the method mentioned is tying into a system that is BCM program and really not advisable.
If you have a BCM or ECU issue and it is shown that you used a tie-in power source as mentioned above, it could void your warranty regarding not only the BCM but the PCM as well.

Don't be lazy when it comes to adding electrical depended poser accessories and do it correctly.

Remember every thing change when OBDII and CANbus came into use in 1995.