Subaru Ascent Forum banner

Another Approach to Dashcam Mounting

7.8K views 7 replies 5 participants last post by  ohmbroo  
#1 ·
Thought I'd share some comments and detail concerning my Dashcam implementation and mounting in my 2023 Ascent Touring. The Dashcam model is the BlackVue DR900S-2CH with the Power Magic Pro (PMP) accessory to provide for Parking Mode operation. So there were several issues to tackle: 1) Location consistent with Eyesight Forbidden Area Rules, 2) Wife mandated requirement for no visible wires and 3) The need for two 12V taps - one switched and one constantly on for the PMP parking mode state.

Addressing the first of these requirements, the Eyesight restrictions, I was able to take advantage of the more relaxed limits of the 2023 Eyesight camera arrangement. After studying discussions on this site as well as many on the Outback, Forester and Crosstrek sites, I became convinced that the best way to verify that my mounting arrangement did not degrade the Eyesight capability was to actually test the impact using Eyesights ability to report a disabling problem. To wit, I mounted the forward DR900S unit with temporary adhesives and proceeded to test daylight, twilight, dusk and nighttime driving conditions of the Adaptive Cruise Control, the Autodimming Headlight System, the Lane adjust system and rapid close approach frontal problems (using bushes). Firstly, I did these tests without the Dashcam mounted, discovering where Eyesight switched off posting its alert, then with the Dashcam mounted. In the end, my preferred mounting position on the camera cover behind the rear view smart mirror (see picture) showed no difference in Eyesight response compared to it not being present.
Image


I include this picture to show the relationship to the rear view mirror, the placement of the PMP and to show the actual exposed wires in the arrangement (look between the PMP and the dash cam). Also notice that the Blackvue notation on the Dashcam is upside down. This is because I have it mounted so the wire connections enter on the Driver's side. This Dashcam has an internal GPS system, so the only connections required are DC power and the video coax from the rear camera.

For the second "no visible wires" mandate, I snaked the coax wire to the driver's left under the headliner, down the A-piller (on the door side to minimize overlap with the airbag) to the door sill opening, then along the door edge flooring to the 3rd row seating zone, then up the trim to edge defined by the plastic/ fabric interface and back to the lift gate trim. Threading the coax cable through the flexible channels to the lift gate was very straightforward using the WD40 technique described by many others, after the trim panels were removed. The excess cable length was left in the metal void in the lift gate structure. The rear camera was mounted in the area covered by the wiper blade clearing the SmartMirror camera.

The second part of no visible wires involved tapping the Ascent system for continuous and switched 12V. Here I tapped the Smart Mirror plug using the clever Dongar adapter first described (to my knowledge) by "madtowner" in his August 2023 comment in the thread entitled "Dash Cam?". This adapter inserts through a clean plug-in into the connector feeding power to the Smart Mirror and brings out to a modified USB-A connector the switched 12V feed power line for the mirror. The adapter I used is the 10 pin Toyota/Subaru device sold on the Dongar.com website. However, a judicious review of the wiring diagram for the 2023 plug supplying the Smart Mirror shows that pin A1 supplies switched power from fuse 19, pin A2 supplies system ground (these are the two wires brought out by the Dongar adapter) AND pin A6 has the continuous 12V feed from fuse 14. The Dongar adapter conveniently runs discreet wires between all 10 pins of the inlet and outlet connectors. Consequently, I made a new adapter containing the two original output wires and added my tap from pin A6 for my required three lines of continuous, switched 12V and ground.

Now there are often wire tapping objections from electrical engineers and I am only a retired scientist - no engineer. However, a few facts need to be considered. Inspecting the wiring diagram, Fuse 14, the source of continuous 12V, supports the Combination Meter, the Auto Headlight LevelerControl Module (CM), the Immobilizer CM, the Electronic Parking Brake switch, the REAR VIEW MIRROR, the Power Rear Gate CM, the TPMS and Keyless Entry CM, and the Eyesight Stereo Camera. Fuse 19 supports the Electronic Throttle ControlRelay, the Power Rear Gate Module, the TPMS and Keyless Entry CM, the RAB CM, the Left and Right Radar Sensors, the BSO switch, the Hazard switch, the REAR VIEW MIRROR, the Rain Sensor, the Glass Roof Control Module, the Shade Control Module, the Eyesight Stereo Camera and the Stop and Brake switches. In my test of Fuse 14 and Fuse 19 loads, the maximum current I have observed is 5.5 amps at 12.6V. Both fuses are rated at 10 amps. The Blackvue DR900s-2CH with both cameras recording to the embedded microSD card and with GPS activated and local WIFI, draws 0.364 to 0.411 amps at 12.55V (my measurements) for a total of 4.57 to 5.16 watts. I believe the additional camera load on these circuits is a minor addition to nominal operating load on the circuits of fuse 14 and 19. Finally, I will operate the Power Magic Pro device with settings for battery cutoff at 12.0V and for a maximum parking mode record time of 6 hours.

So, with the removal of the ceiling switch console with the map lights and a twist of the Smart mirror, I accessed the discussed power plug and then ran the three needed wires under the camera assembly and along (with cable ties) the camera feed wires in the area protected by the third camera cover. I bored a hole in that cover, sealed with matte duct tape and ran the wires down to the PMP module. System Completed. Adding a few additional pictures for some clarity.

Image



Image


Image
 
#2 ·
...
Addressing the first of these requirements, the Eyesight restrictions, ...Firstly, I did these tests without the Dashcam mounted, discovering where Eyesight switched off posting its alert, then with the Dashcam mounted. In the end, my preferred mounting position on the camera cover behind the rear view smart mirror (see picture) showed no difference in Eyesight response compared to it not being present. ...
I am curious if you have tried other places on the windshield to see which places are better or if you simply confirmed that mounting the way you did (behind the rear mirror) did not interfere with Eyesight. Some of us mounted the camera to the left or right of the Eyesight cameras. I mounted to the left and have not seen any error message so far. I do get warnings when the car in front of me pull away, cut into my lane, and the ACC works well ... etc ... However, whether the Eyesight performs at its 100% efficiency as designed seems impossible to know without some instrumental measurements.
 
#3 ·
Actually, after studying the 2023 Eyesight restricted zones, I concluded that the far left or right windshield areas were a permitted backup plan. I did focus on the cente-aligned-back-of-mirror area as it was my first choice. Of course, you are definitely correct that verifying 100% (or 95% or ...) can't be done without an extensive engineering analysis and field testing! My justification was that the interference areas were justified on the basis of reflections. The cylindrical matte surface of the BlackVue suggested suggested minimal focussed reflectivity, but no way to verify. Clearly, the left or right windshield mount is a safer bet given the Eyesight engineering suggestion.
 
#4 ·
Just another detail addition. The supplied coaxial cable supplied by BlackVue for the connection to the rear camera was 6M (about 20 ft) long and wasbtoo short for thevfull run to the lift gate given the Ascent length and my floor transit approach. The coax connectors are MCX units and I purchased an extension kit consisting of 2-1M long extensions at Amazon (Oiyagai 2pcs RF RG316 Pigtail MCX Antenna Connector)which gave me an 18" excess.
 
#5 ·
I originally wanted to mount my dashcam on the back of the mono camera housing also, but the design of the cam didn't have enough angle adjustment to compensate for the aggressive angle of the black housing, The camera was aimed at the sky. Until I can fabricate a shim that will correct the angle, I have the cam mounted directly below the mono camera. The central position low enough to see past the rearview mirror is neccessitated by the rear facing camera. I have had it mounted this way since taking delivery in May and there haven't been any known Eyesight interference.

I also have another dashcam with a similar architecture as the Blackview mounted just below the black dots at the top of the windshield just to the left of the driver side Eyesight camera. Even with 2 cameras mounted, the Eyesight has responded as expected. YMMV.

For the curious, using 2 cameras because I am testing a known quantity against a prototype.
 
#6 ·
A bit of blither I contemplated aiming/scanning a laser at the BlackVue camera and the Power Magic Pro box while operating with Eyesight to see if there were any reflection path sensitivity, but Eyesight only operated with active car at a bit of velocity - so too dangerous to try!
 
#7 ·
I put a Garmin Navi-cam in the lower left portion of my 22 Ascent. While checking the owners manual(s), there was a “forbidden” zone shaped like an inflated “T”. The extreme lower left and right were not in this forbidden zone. I have had it there, power cable run to between the door jamb and dash, for more than two months (and hundreds of both city and highway miles, without issue. The power cable is run along the storage shelf, over the steering column, to the power outlet center counsel.