Guide: 2nd Generation CX-9: Running cable for rear dashcam

sm1ke

2018 Mazda CX-9 Signature
Moderator
Contributor
:
Canada
A little while ago, I was made aware of the fact that I had incorrectly run the rear camera wire (and the original front camera wire to the 12v socket) over the curtain airbag in the A-pillar. This is not ideal, as the wire would interfere with the curtain airbag deployment if the airbag were to go off. In light of that, I decided to remove the cable and run it properly and safely. I have edited to original instructions to reflect the proper way to run the cable down the A-pillar. Thanks Anchorman for the heads up.

This is a DIY How-To for a rear dashcam installation for the 2nd Generation Mazda CX-9. Please note that this guide is mostly just to show how I ran the power cable from the front camera to the rear camera. With this particular front and rear dashcam combo (Viofo A129 Duo), the rear camera transfers data and gets power from the front camera via a single cable. In this particular install, my front camera is hardwired to the Homelink-enabled rear view mirror using an Invisicord (more details found here).

This process was documented/photographed by myself, using my crappy cellphone camera and my 2018 Mazda CX-9 Signature as the "demo" vehicle. This DIY is provided as a learning aid and reference guide. I assume no responsibility for warranties you may void or any damages you may inflict on yourself or your vehicle.

As mentioned perviously, the camera set I installed is the Viofo A129 Duo. Both front and rear cameras record in 1080p 30 FPS (if the rear is disconnected, the front changes to 1080p 60 FPS). It takes still photos, and has a mic. Along with other standard features, it has GPS and Wi-Fi functionality, and can accept up to a 256gb microSD card. Viofo has stated that the best cards to use for their dashcams are Transcend High Endurance. Samsung Pro cards also work well, but they will not honor the 10 year warranty if the card is used for "surveillance recordings". Since both cameras write to the single card in the front camera, it makes sense to splurge for the higher capacity SD cards designed for dashcam use. I went with a 128gb card. Moving on..


What you'll need:

- Flathead screwdriver w/ rag to prevent scratches, or a pry tool
- Wire fish tool (I made my own out of BBQ skewers and duct tape lol)
- 8m extended cable from Viofo (or comparable 8m cable if your rear cam is not a Viofo)


1. Figure out where you want to mount the rear dashcam on the rear windshield. Be sure that you take into account the cords that may plug into the camera and the cards that may be installed/removed, and leave adequate space around the camera to make those areas easy to access. If your camera has a video display, you can connect the power cable and turn the car on, then mount the camera using the video output as a guide. Ensure that the double-sided tape does not cover any rear-defroster lines. Covering these lines may cause issues with the defroster functionality, and removal of the double-sided tape could damage the defroster lines. After mounting the camera, turn the car off.


2. Since my rear cam is powered by the front cam, I ran the wire from the front camera through the headliner on the driver's side. There's plenty of room to push the cable into the headliner without removing anything.


3. Pull down the weatherstripping (1) on the A-pillar, then gently pull the A-pillar cover (2) loose by gripping at points (A) and (B).

attachment.php


Note that the A-pillar cover will not pop off completely. This is because there is a plastic tether that holds the cover to the frame of the car. The tether is there so that if the curtain airbag deploys, the cover doesn't go flying. The tether can be removed without cutting it, but it requires some patience and some needle nose pliers. You would simply twist the clip (3) and thread it through the hole. During my install, I chose to leave the tether intact and just work around it.

attachment.php



4. With the A-pillar cover loose, you'll need to pull it up and towards the back of the car to create room for the dashcam wire to run. This is much easier to do if you have removed the tether, but it can still be done with the tether still fastened. Move the cover to the side.

attachment.php



5. Run the dashcam wire from the headliner down the A-pillar, making sure that the wire does not cross over the airbag (4). I ziptied the wire to the existing wire loom (5) to make sure it didn't fall in the path of the airbag.

attachment.php



6. Replace the A-pillar cover (installation is the reverse of removal). Run the wire down to the footwell area, tucking it behind the weatherstripping (6) as you go.

attachment.php
 

Attachments

  • A-pillar1.webp
    A-pillar1.webp
    9 KB · Views: 1,495
  • A-pillar2.webp
    A-pillar2.webp
    9 KB · Views: 1,509
  • A-pillar3.webp
    A-pillar3.webp
    9.1 KB · Views: 1,495
  • Tether.webp
    Tether.webp
    7.9 KB · Views: 1,518
  • Wirefish1.webp
    Wirefish1.webp
    11.2 KB · Views: 1,499
Last edited:
7. Using your screwdriver or pry tool (wrap the end in an old t-shirt or something if you want to prevent scratches), insert one end into the groove (7) and pry the step cover up. This piece is held on by plastic and metal clips. Once you get your fingers underneath you can easily pull it off by hand.

8. Open the rear door and remove the step cover (same as the front). Use your wire fish tool to pull the wire from the front to the rear. I found that I encountered less resistance by threading the wire along the right side of the wire loom (8).

attachment.php



9. Run the wire under the floor mat and behind the seatbelt anchor, then run the wire between the 3rd row seat and the plastic panel to the trunk.

attachment.php



10. Remove the cover from the cubby, then run the wire around the outside edge of the cubby (9) and into the weatherstripping (1O).

attachment.php



11. Run the wire up the weatherstripping to the headliner. You have an option here. If you have the patience, you can try to thread the wire through the tubing on the right side of the hatch (as vitpk1 did in the post following this one). I personally found that I didn't have enough room for that unless I dropped the headliner. Instead, I simply had the wire come out from behind the weatherstripping (11). I may attempt this at a later time.

attachment.php



12. Remove the liftgate cover. This piece simply pulls right off, and is held in by metal and plastic clips. The red arrows show where some of the clips attach. Connect the power cable to the rear camera. Replace the liftgate cover by pressing down on the areas identified by the yellow arrows.

attachment.php
 

Attachments

  • Wirefish2.webp
    Wirefish2.webp
    14.1 KB · Views: 1,511
  • Wirerun1.webp
    Wirerun1.webp
    12.2 KB · Views: 1,430
  • Wirerun2.webp
    Wirerun2.webp
    12.7 KB · Views: 1,455
  • Wirerun3.webp
    Wirerun3.webp
    12.5 KB · Views: 1,456
  • Liftgate.webp
    Liftgate.webp
    55 KB · Views: 1,548
Last edited:
You can run your cable on the inside of headliner, that would free enough cable.
This is how I did it, and just secured with duct tape to prevent rattling. ( my setup is little different: Viofo 119S up front and Blueskysea in rear, but I ran power cable from the front this way):
93cbd1dc7c88b394357deb2a52b7ae62.jpg

Also I ran my cable through Right rubber boot, as it has more room due to only been used for rear window washer sprayer line)
fee50953139463be7dc1da5424a907ac.jpg

83291e42cd1330d9ddcd644a5983c397.jpg
 
You can run your cable on the inside of headliner, that would free enough cable.
This is how I did it, and just secured with duct tape to prevent rattling. ( my setup is little different: Viofo 119S up front and Blueskysea in rear, but I ran power cable from the front this way)

Thanks for those pics vitpk1. Did you run the power from the front headliner all the way to the rear (without going down the weatherstripping and through the step channels)? If so, I'll definitely do that instead.

That rocks! Thanks for taking the time and effort to post.

Happy to :)
 
I did run power from fuse box ( used tap a fuse adapter), single 12V to 5V adapter, than spliced power cords for the front and rear dash cams, ran it up the pillar and secured to the inside of the headliner( one power cord for the rear all the way and one cord towards the rearview mirror).
dfc6f3592acd2f7e4deaddcd5943b84b.jpg
 
Last edited:
Hi,

Can you please provide where and which fuse adapter you used and are you able to guide me through the process?

Thanks :)
 
I did run power from fuse box ( used tap a fuse adapter), single 12V to 5V adapter, than spliced power cords for the front and rear dash cams, ran it up the pillar and secured to the inside of the headliner( one power cord for the rear all the way and one cord towards the rearview mirror).

Perfect, thanks. Sounds like the whole wire fish step can be avoided, which is nice because others won't have to go through what I went through (made my own wire fish by taping three chopsticks together and putting a twist tie on one end, lol).
 
*post deleted due to incorrect cable routing*
 
Last edited:
vitpk1, how did you remove the screw in the headliner (shown in this pic, with your index finger pointing towards the hole)? It looks like one of those fasteners where you use a flathead to lift the center, and the entire screw pops out, but I didn't see a spot to insert a screwdriver.

93cbd1dc7c88b394357deb2a52b7ae62.jpg
 
@sm1ke I copied your routing and managed to hide all the cables save for the bit that goes into the cam itself. For the B pillar if you pull back the weather stripping there is a gap that you can run the cable through.

I wish I knew how to pull down the headliner a bit. What I had to do was run it along the hatch weather stripping and then up towards the cam. I had to make a small slit to the weather stripping so the cable does not pull it upwards when opening the hatch.
 
You do realise that crossing the top of the A pillar is extremely dangerous? If the airbag isn*t torn apart if it needs to deploy then somebody is going to get maimed by the trim or the wire when it hits them in the face. It*s airbag failure, whipped with a severed wire or hit by trim at explosive speed, which do you prefer? The trim is tethered to the A post so that it stays in place but it has no option but come off as you*ve tied it to the airbag.

It is possible to cross under it safely but that trim has to come off to do it. The official Mazda way is to cut the tether and fit a new one but you can get it off if you are careful and reuse it. This shows you how but if you make a mess getting it off, just buy a new one. It*s not worth the risk.


Oops, no, Ive just realised youve done it again on the B pillar. The only safe way is to down under the doors and come up somewhere in the trunk. Ironically the legal reminders that you are interfering with the air curtain are clearly shown in the photos! If you run out of wire you can buy a 10ft extension off amazon or eBay.

https://youtu.be/6Y85r6yEhTM
 
Last edited:
To get those trim clips out you just pop the centre part out with a small screwdriver and then the main body of the clip will just fall out.
 
You do realise that crossing the top of the A pillar is extremely dangerous? It is possible to cross under it safely but that trim has to come off to do it. The official Mazda way is to cut the tether and fit a new one but you can get it off if you are careful and reuse it. This shows you how but if you make a mess getting it off, just buy a new one. It*s not worth the risk.

Oops, no, I*ve just realised you*ve done it again on the B pillar. The only safe way is to down under the doors and come up somewhere in the trunk. Ironically the legal reminders that you are interfering with the air curtain are clearly shown in the photos! If you run out of wire you can buy a 10ft extension off amazon or eBay.

https://youtu.be/6Y85r6yEhTM

I appreciate the heads up, but you could be less of an ass about it. I edited your original post above so you could see how. It gets the point across without the sass.

Thanks for posting (and making) that vid. At the time, Viofo did not sell an extension for the rear cable, and you can't just use any USB extension as the cable is proprietary. Viofo does now sell an 8m cable, which I just ordered. I'll use your video if I end up running the cable through the cabin instead of through the headliner.

To get those trim clips out you just pop the centre part out with a small screwdriver and then the main body of the clip will just fall out.

The headliner clip I'm talking about doesn't have a center part that can be popped out with a screwdriver.


I'll leave the instructions as is, and I'll update them after I've rerun the new cable.
 
I*ll consider myself told off!

Hats off that you*ve taken it onboard. I*d hate anybody to get hurt - experiencing an accident bad enough to deploy the airbags would be bad enough without any unexpected add ons.
 
I*ve found this in the file for the US CX5. They are concealed Clips that you pry down with a screwdriver.

B533666-D-69-E6-435-F-AC69-5460-B472-CDEE.png
 
Curiously the European model has the two part clips. It seems hard to believe there are two versions but I*ve had my headliner down for the same reason and the definitely are........

AA57344-C-AB49-4-D63-B5-E0-F6-A50-B5-B2-E62.png
 
I*ll consider myself told off!

Hats off that you*ve taken it onboard. I*d hate anybody to get hurt - experiencing an accident bad enough to deploy the airbags would be bad enough without any unexpected add ons.

My safety comes before my ego :) Thanks again for bringing this to my attention. In my eagerness to install the rear dashcam, I completely overlooked how running the cable the way I was would interfere with the side curtain airbags. I think that I'll remove the sections that detail the incorrect cable routing to prevent any others from making the same mistake.

Also, for those who have subscribed to this thread (through active posting or otherwise), I'd urge you to carefully remove the wiring if you routed it that same way I had, and instead rout the cable down the A-pillar (instead of across it) and through the channels below the door sill plates. I removed the rear cable as soon as I got home that day, but didn't have time to update this thread as I went on a short weekend road trip with the family.

I*ve found this in the file for the US CX5. They are concealed Clips that you pry down with a screwdriver.

B533666-D-69-E6-435-F-AC69-5460-B472-CDEE.png

Ah, thanks for that image, that helps a ton. Have you dropped the headliner in your CX-5 before? I wonder if I can get enough room to fish the wire through, just by removing the clips and supporting the headliner..
 
Sorry for the late reply. I have but mine has the two part clips. I didn*t come from the front because I have two independent cameras so I came from the rear trunk power supply, around the door frame and then into the umbilical like you did. I would add that for euro models of either the 5 or 9, that if it has a digital (DAB) radio, use a screened cable and go through the left side umbilical as in your tutorial as the antenna goes through the right and it will otherwise stop it working.
 
Original posts updated with cable run down the A-pillar instead of across it. Thanks again Anchorman.
 
Back