Key install workflow
I dropped the headline by removing the 10mm bolt hiding behind the dome light module above the rear-view mirror and hid the dashcam wire above the headliner. I left one screw fastening a small connector to the air-bag display module undone as it was annoying to get back in. At the a-pillar the rear dashcam wire runs deviated paths from the main dashcam wiring harness and ran towards the posterior of the car following the door opening channel underneath the weather stripping. The main wiring harness for the dashcam ran down the length of the a pillar and was fastened in the same retaining loops as the OEM wiring found in this area, well out of the way of the curtain airbag. The dashcam wiring then made its way to the driver side footwell fusebox through the door channel. At the fusebox, the BAT+ (constant 12v) dashcam wire is attached to the fusebox (Fuse f7) with a 10A jumper, taking great care to ensure the wire side of the jumper was opposite the hot side (12v constant) on the fuse bridge, guaranteeing that current needs to pass through the fuse before making its way to the dashcam. To fasten the ground, I unscrewed a large bolt at the base of the A pillar using channel lock pliers instead of a wrench (scratching up the head of the bolt significantly) and bent the open ended wire terminal to fit nicely under the hold. The ACC power was connected to BCM (body control module) wire 2AE (which was yellow instead of white in my car) using a vampire wire splicer.
The rear dashcam was installed by running the wire along the length of the driver side window, branching from the main wiring harness at the top of the A pillar under the headliner. The wire is nested under the driver and passenger window weatherstripping, merging the two behind the B pillar. To reach the hatch, the wire was run under the headliner in the trunk area, and into the hatch through a weatherstripping grommet for hatch power accessories (defrost, wiper etc.). Running this wire through the grommet was challenging and time consuming, and eventually required all connections running through the passenger side grommet be disconnected to allow for sufficient flexibility and access to snake the dashcam wire through. Once inside the hatch, running the wire to the dashcam neatly was trivial.
Problem areas
During the initial install, I accidentally attached the 12v contsant BATT cable to the BCM ACC wire (2AE) and on the second startup the car threw a CEL and killed signal to that wire while car was running or when the ACC mode was initialized. I suspect the dashcam was drawing excessive amperage from the BCM wire instead of the fusebox and the car dynamically disabled this output to prevent any issues. Realizing my mistake, I cleared the CEL manually and unplugged the car battery for 15 minutes to reset the ECU. After this reset, wire 2AE started reading 12v as normal with the car on and in ACC mode.
Finally I spliced the ACC dashcam wire as originally intended to wire 2AE and BATT+ to the fusebox with the 10A fuse jumper. The splice I made for the BATT+ cable to the fusebox is not great as I twisted two wires together and melted heat shrink together, I should replace this splice with a crimped connection as the connection was initially not feeding power to the dashcam when I remounted all the interior trim covering the fusebox. On the other hand, I crimped the BCM 2AE to ACC power connection using channel lock pliers (which might be a point of failure) and a nice 16 AWG crimp connection.
When running the wire to the rear hatch through the flex-grommet, I removed both the car and hatch side connections. I noticed that one of the 4 teeth holding the grommet firm to the car was deformed and appeared loose after removal. There is a possibility, hopefully extremely remote, that these grommets may not form an entirely firm seal around the body of the car and allow for some water to enter through the junction. That being said, upon reinstalling the grommets they appeared entirely properly seated and I suspect the deformed plastic tooth is still performing as intended. Worst case scenario these grommets can be replaced. Additionally, the rear dashcam is held to the glass with double sided tape. This connection appears reasonably secure at the moment, but I suspect long term heat exposure will lead to reduced adhesion requiring eventual substitution.
Long term improvement
The fiasco with power being blocked to wire 2AE on the BCM and subsequent CEL convinced me that drawing ACC power from the BCM is probably not a great idea as there is no fuse to protect the circuit. As such I would like to connect the ACC power on the dashcam to an ACC enabled circuit on the main engine fusebox (F47) using a mini fuse adapter. This ACC line originating from F47 can then be used to feed both a subwoofer and the dashcam and the BCM 2AE vampire splice can be abolished entirely. It makes the most sense to run both wires through the firewall grommet when I proceed with the subwoofer install in the future.
There’s no way around it, the rear dashcam is downright ugly to look at through the rear-view mirror, resembling an inverted droid tethered by a wire. It looks cheap, it’s unsightly, we want it clean, neat and demi-professional! I found a nice 3D printable enclosure that should take care of this issue, and encase the ugly, cheap camera in a nice plastic shroud that doesn’t quite irritate the eye. Long term both the 3D printed enclosure and camera can be mounted directly to the large, thin plastic trim piece with a few small screws or some serious adhesive.
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