[millermmail]

I need some help please gentlemen.

On my step down converter, we have the red and black wire.

on the dimming mirror harness, I have the 3 wires (black with white stripe with is +12v, middle which is the ground and the black on the end).

I imagine I connect the black with white stripe to the red wire.

Which wire do I connect to the black wire on the step down converter? The middle ground wire or the one on the end?

Thanks
James

Do you have a picture?

On the mirror harness, there should be ground, +12v accessory, +12v reverse-signal. You want to hook into ground and +12v accessory, tape off or ignore +12v reverse.

On the converter, I have seen 2 possible configurations:
12v Input, Ground, 5v output
12v Input, Ground input, 5v output, Ground output

Determine which is which (per it's directions) and hook the red input to +12v accessory, ground to ground, +5v output to the camera, and camera ground to either output-ground (if available) or the car ground (if the adapter has no output).

If you post pictures, it'll be easier to understand your issue.

 

[bwoodworth]

Thanks for the great write up on this. I am considering mounting a dash cam the same way, but I have a couple questions. I have a auto dimming mirror so the 3-pin connector is being used for that. Is it possible to wire up a dash cam as well without splicing into the wires going to the mirror? If I have to I will, but would rather have the option to go back to stock if possible. If I get and extra harness is there a way to split it so the mirror can plug into it and also splice of the extra harness? Also, I saw the question earlier about whether or not having both hooked up would draw too much power and over heat something. Does anyone have an answer to that?

 

[millermmail]

I would not worry about power consumption, it will probably be under 1/2 amp for the camera.

What model car specifically? You may need to look at the connectors in the roof first, I found mine (2012) was fifferent than my parents (2013/2014) even though they are all 3.6R Limited w/ sunroof and backup camera.

I suggest if you need to splice, add a new power connector and then plug the camera into that. I did that for my parents cars which had no connector in the cieling at all.

 

[bwoodworth]

I have a 2014 Outback 2.5. It does have the HomeLink mirror.

 

[millermmail]

I am going to guess thats the same as my parents 2014 3.6R with homelink mirror then, there was no connector in the roof (only the back of the mirror) so I had to splice the wiring harness in the headliner. I added an Anderson Powerpole (because I had them handy and they were smallish) connector and then ran the camera from that.<br />
<br />
I will say they have had no issues so far as I know with powering both camera and mirror from the same wire.<br />
<br />
I can't remember which wire was what color but there were +12, key switch, reverse, and ground. I had to locate all of them because the reverse behaves like ground when its parked. I tapped the key switch +12 and the ground only.

 

[bwoodworth]

There is a three pin connector in the roof.

It looks like there is one wire with a white stripe and the other two are black. I have a multimeter so I can check each of them. Sounds like I just need to find the +12 and ground?

 

[error]

In this case, the ground wire should be in the middle, and +12V acc is black with gray stripe.

Be careful with the multimeter: I accidentally shorted the leads and blew the 5A fuse.

 

[millermmail]

There is a three pin connector in the roof.

It looks like there is one wire with a white stripe and the other two are black. I have a multimeter so I can check each of them. Sounds like I just need to find the +12 and ground?

Interesting. The 2014 my parents had did not have that connector (but my 2012 did).

What trim package do you have, and do you have any extras like blindspot-monitoring?

Yes, in that case you will have +12, Ground, Reverse.

Here's the procedure I used to figure it out using a multi-meter:
1. Set the parking brake so you can't roll, and turn the key to "run" so the dash lights up and dings (don't need the engine, this way you won't try and drive away accidentally)
2. Connect the black multi-meter lead to something bare metal on the car for a ground (door latch is easy to reach)
3. Touch the positive meter lead to each of the three pins, careful to touch only one at a time with the probe (don't short across 2 of them). You should find one +12 and the other 2 appear "dead". This is your key-switched positive, take note of it.
4. Shift the car into reverse (but don't let it roll).
5. Repeat your measurements on each pin. You should find two +12 and one appears "dead". The one that appears "dead" is the ground, take note of it.
6. Shift into park and shut off the key

Now you should know exactly what 2 wires you need to splice.

It's possible you may be able to order a cable on eBay to avoid splicing if you can figure out what mirror you have exactly. There was a very friendly and helpful seller I worked with he advertises "most cars to most mirrors" custom power cables (he sold me a 1/2 wiring harness for my 3-pin plug at reduced cost since I didn't need the mirror connector). I sent him a PM before buying to make sure we both were on the same page and communication was great. My original plan was to have him build me a new "Y-cable" that ran from the 3-pin plug to both the mirror and my camera until I learned that our cars were wired a bit differently. Since yours has the plug, you could probably speak with him about getting a custom cable that you just "unplug" the OEM wire at the mirror and 3-pin then connect the "new" wiring harness with the extra power wires.

Here's the seller that I spoke with about getting a custom connector for the 3-pin plug. If you can talk to him and get pictures of both the car and mirror plugs and explain you want a "Y" cable to power a dash cam from the key-switched power he can tell you if he can build the cable to your specifications.

For those who do have the 3-pin plug, the cheapest I've been able to source a mirror wiring harness from for this mod is this eBay seller:
Subaru Rearview Mirror Plug Play Wiring Harness Homelink Others New | eBay

 

[bwoodworth]

Interesting. The 2014 my parents had did not have that connector (but my 2012 did).

What trim package do you have, and do you have any extras like blindspot-monitoring?

Yes, in that case you will have +12, Ground, Reverse.

Here's the procedure I used to figure it out using a multi-meter:
1. Set the parking brake so you can't roll, and turn the key to "run" so the dash lights up and dings (don't need the engine, this way you won't try and drive away accidentally)
2. Connect the black multi-meter lead to something bare metal on the car for a ground (door latch is easy to reach)
3. Touch the positive meter lead to each of the three pins, careful to touch only one at a time with the probe (don't short across 2 of them). You should find one +12 and the other 2 appear "dead". This is your key-switched positive, take note of it.
4. Shift the car into reverse (but don't let it roll).
5. Repeat your measurements on each pin. You should find two +12 and one appears "dead". The one that appears "dead" is the ground, take note of it.
6. Shift into park and shut off the key

Now you should know exactly what 2 wires you need to splice.

It's possible you may be able to order a cable on eBay to avoid splicing if you can figure out what mirror you have exactly. There was a very friendly and helpful seller I worked with he advertises "most cars to most mirrors" custom power cables (he sold me a 1/2 wiring harness for my 3-pin plug at reduced cost since I didn't need the mirror connector). I sent him a PM before buying to make sure we both were on the same page and communication was great. My original plan was to have him build me a new "Y-cable" that ran from the 3-pin plug to both the mirror and my camera until I learned that our cars were wired a bit differently. Since yours has the plug, you could probably speak with him about getting a custom cable that you just "unplug" the OEM wire at the mirror and 3-pin then connect the "new" wiring harness with the extra power wires.

Here's the seller that I spoke with about getting a custom connector for the 3-pin plug. If you can talk to him and get pictures of both the car and mirror plugs and explain you want a "Y" cable to power a dash cam from the key-switched power he can tell you if he can build the cable to your specifications.

To be honest I don't remember exactly what trim package. It was one on the lot and as far as I can remember it was the lowest model except it had the alloy wheels and the HomeLink mirror.

I ordered a custom harness from the eBay seller you recommended. Basically it is the normal 3-pin to 12-pin connector with a couple extra leads coming of the 3-pin connector for +12v and ground. It should arrive tomorrow with the 12v - 5v converter so I can get started on that.

My biggest issue right now is how to get the original harness out and the new one in. it doesn't seem like there is enough space between the roof and the windshield to fit either the 3-pin or 12-pin connector. Is there any way to pull the roof down enough without damaging it to fit it through?

 

[millermmail]

To be honest I don't remember exactly what trim package. It was one on the lot and as far as I can remember it was the lowest model except it had the alloy wheels and the HomeLink mirror.

I ordered a custom harness from the eBay seller you recommended. Basically it is the normal 3-pin to 12-pin connector with a couple extra leads coming of the 3-pin connector for +12v and ground. It should arrive tomorrow with the 12v - 5v converter so I can get started on that.

My biggest issue right now is how to get the original harness out and the new one in. it doesn't seem like there is enough space between the roof and the windshield to fit either the 3-pin or 12-pin connector. Is there any way to pull the roof down enough without damaging it to fit it through?

Yes, it's a bit difficult but quite doable fitting stuff thru the headliner by the windshield. I say difficult because my philosophy is if something doesn't seem to go easily I usually stop and try to figure out why...which avoids breaking things but I also frequently find out later that I really just didn't try hard enough.

If your mirror has a little plastic "cover" over the wire that seems to slide down (sort of telescope) [strike]to give you more room[/strike] and then unclips (squease left/right carefully) from the mirror mounting base to let you remove the wire to the mirror. It's mostly to make it look nicer, the mirror is actually held onto the windshield with a torx screw mount (don't need to remove it, just be aware it's there).

The existing wire adapter part is likely held to the inside of the headliner with a few pieces of blue or yellow "tape" from the factory that you'll need to work off. Where I encountered this I just worked my fingers along the wire by feel and carefully twisted my finger back and forth until it let go. In all 3 of our cars (2012, 2013, 2014) the wire runs from the mirror into the headliner then sharply to the driver's side to avoid pinching between the roof and the headliner plastic clips, then loops around to the rest of the wiring harness.

To fit things thru the headliner I found it was easiest to put my hand in thru the "hole" where you moved the maplight control panel and "pull" down from the metal ceiling. I also recommend disconnecting the maplight/glasses-holder panel so it is safely out of your way giving more room to work (and if you slip pulling you won't hit the dangling stuff). Don't pull where it's at the edge, I suspect the material isn't that strong and could tear but if you pull with both hands [strike]work your hand in where it resists[/strike] (between the metal roof and [strike]where it has resistance[/strike] the plastic part) it will eventually start to move when the plastic "one way push pin" gives way. If the plastic rivet breaks it is likely not too serious since the glasses holder thing screws into the metal ceiling and will hold it all together, mine didn't break but doesn't hold well either from my mucking with it so much..

I honestly don't know what holds it up but I recall it took moderate effort to make it budge. It's easier to feed things from the inside down to the windshield rather than the other way in my experience, I was able to fit even the big ferrite choke on the USB cable thru so the smaller connectors should be easier. It will probably get hung up a bit where the headliner "curves" up to meet the windshield, I had to make a few tries. Small fingers are helpful (I have small hands for a guy but it was a tight fit).

Since you have the old harness you can probably tape the "mirror" end of the new adapter to the "3-pin" end of the old one and use that to pull it thru easier while holding the headliner, then the old wire will act like "fishing tape" for the new one.

Once you finally get stuff fed thru and connected remember to check the wires aren't pinched where you push the headliner back up and "slide" the little plastic thing up in place (it fits in a small notch in the headliner) to hide the wires that run to the mirror.

If time permits later today I'll try and get a few pictures [strike]or video[/strike] to explain what I think I did.

EDIT: I got some pictures but I can't upload them until tonight when I get home, Verizon is being silly slow so they are stuck in my phone. I've updated my details with bold italic in the meantime.

 

[millermmail]

I apologize for the lateness of these pictures...but here's a bit more detail showing how everything comes apart leading from the headliner down to the mirror.

The "tube" covering the wire to the mirror slides down (telescopes) and then unclips from the mirror mount.

I recommend unplugging the wires to get the "panel" out of the way, mine had 3 connectors to disconnect.

Then it's just a matter of pulling down on the plastic part, here you can see I eventually got it pulled down far enough you can see the blue light from the windshield coming thru the gap. In the one picture you can almost make out the yellowish tape holding the wire to the inside headliner where it comes up from the mirror.
The other thin "lose" wire you can see going to the windshield is the USB cable powering my dash cam.

 

[bwoodworth]

Thanks for the detailed pictures. I was afraid of pulling the plastic too hard to pull it away from the roof, but I just did it gently and the tab popped out and I can slide the cables through easily.

I have it all hooked up and the dash cam works great. It powers up and starts recording right way when I turn the car on. Is there any way to configure it to turn of the display though? It is tucked behind the mirro so it isn't a big deal for the driver, but is annoying for the passenger especially at night. I have the Novatek A115 mentioned in the OP.

 

[millermmail]

Thanks for the detailed pictures. I was afraid of pulling the plastic too hard to pull it away from the roof, but I just did it gently and the tab popped out and I can slide the cables through easily.

I have it all hooked up and the dash cam works great. It powers up and starts recording right way when I turn the car on. Is there any way to configure it to turn of the display though? It is tucked behind the mirro so it isn't a big deal for the driver, but is annoying for the passenger especially at night. I have the Novatek A115 mentioned in the OP.

EDIT: Apparently I can't read.

I'm not familiar with that camera, it's possible they do something like Garmin and use a nonstandard USB charge pinout. It's also possible they may have a menu for display timeout.

For my parents' car (Garmin Dash Cam 20) my solution was turn the brightness all the way down and forget about it.

 

[bwoodworth]

I figured out a solution. For others who may be curious there is a screensaver setting on the camera: Off / 1 min /3 mins. I set it to 1 min and the screen and lights shut off after one minute.

 

[waylo]

Thank you everyone for documenting your efforts. I have a 2008 Outback Sport (Impreza) and thanks to the tutorial here, I am on my way to hardwiring my dashcam. I opened up my dome light cavity and found the corresponding 3-wire connector. I have a few parts on order to complete the project. The one thing I spent more time deciding was which DC step-down converter to purchase, given the numerous discussions of noise on here and on Amazon. I finally went with this one:
https://www.amazon.com/gp/product/B016XI9CZQ/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Here is a photo of my 3-pin connector:

There is a middle black wire = ground.
Then there is a yellow+?brown or red on one side, and a yellow+green wire on the other side.

According to some wiring diagrams I found online, the yellow/green one is the accessory wire.

In the original post, @error wrote:
"The mirror harness has a corresponding 3-pin connector on the car side, and 7-pin connector on the mirror side. Harness wires are all black, +12V acc is black with gray stripe, and ground is in the middle."

It's unclear if the black+gray wire is on the car side wiring 3-pin, or on the harness wiring, as there were no clear photos on the 3-pin wires on the car side. Can you clarify?

Regardless, I should take the harness wire that corresponds to the Y+G side and connect that to the red dc converter wire, correct?

 

[error]

Thank you everyone for documenting your efforts. I have a 2008 Outback Sport (Impreza) and thanks to the tutorial here, I am on my way to hardwiring my dashcam. I opened up my dome light cavity and found the corresponding 3-wire connector. I have a few parts on order to complete the project. The one thing I spent more time deciding was which DC step-down converter to purchase, given the numerous discussions of noise on here and on Amazon. I finally went with this one:
https://www.amazon.com/gp/product/B016XI9CZQ/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Here is a photo of my 3-pin connector:

There is a middle black wire = ground.
Then there is a yellow+?brown or red on one side, and a yellow+green wire on the other side.

According to some wiring diagrams I found online, the yellow/green one is the accessory wire.

In the original post, @error wrote:
"The mirror harness has a corresponding 3-pin connector on the car side, and 7-pin connector on the mirror side. Harness wires are all black, +12V acc is black with gray stripe, and ground is in the middle."

It's unclear if the black+gray wire is on the car side wiring 3-pin, or on the harness wiring, as there were no clear photos on the 3-pin wires on the car side. Can you clarify?

Regardless, I should take the harness wire that corresponds to the Y+G side and connect that to the red dc converter wire, correct?

Correct. The red wire goes to +12V ACC, black to ground.

BTW, it seems that the wire colours are different on Impreza. OB 2014 Convenience Package colours: "Yellow with blue stripe - +12V accessory power (connected to the 7.5A fuse #6 in the fuse box under the dash), Black - ground, Black with green stripe - +12V backup lights." As others have said, upper trims may have a different roof harness.

 

[waylo]

Thanks. I received everything today and put it together tonight, and so far it works great! (wasn't paying attention and almost cut the WRONG end of the mirror harness--that would have been very silly!)

I took some more pictures for other folks of the mirror harness:



On this harness it has 2 black wires and 1 black/white wire, which lines up with the +12v accessory.

Rather than soldering and shrink wrapping, I used 2 twist on wire connectors. Not nearly as sturdy, of course, maybe I'll solder and wrap later.

My dc converter was a bit larger but well built. I hooked up my USB multimeter to check the output. It put out a very steady 5V and was drawing 0.34a when connected to my dashcam. Not sure if that is all my dash cam needs, or all it could produce =/.

 

[waylo]

@error and @millermmail wondering if you can comment on a new development.

With my install, described in the previous posts, my left signal clicker is going haywire. It will click at 2-3x normal speed. The rear turn signal light will light up correspondingly, the front does not. This obviously is a safety issue!

When I disconnect the mini-USB connection to my dash cam, this issue disappears.

Any ideas?

 

[millermmail]

@error and @millermmail wondering if you can comment on a new development.

With my install, described in the previous posts, my left signal clicker is going haywire. It will click at 2-3x normal speed. The rear turn signal light will light up correspondingly, the front does not. This obviously is a safety issue!

When I disconnect the mini-USB connection to my dash cam, this issue disappears.

Any ideas?

That's very bizarre. I don't have an answer but maybe these questions will help us figure something out. The only things I can think of off hand is if the wiring isn't what we all think it is, or if the camera or power-adapter is generating some strange interference that's confusing "something" (but darned if I can tell what right now).

Do you have any way to verify (test-bulb or volt-meter) the 12V wires you hooked up to are steady 12V regardless of whether your turn signals are on or you are in reverse (so the backup-lights come on) or park?

What happens if you turn on the 4-way-flashers (hazard lights)?

What model dash-cam (and what seller if it's not name-brand) did you get?

Can you plug a different USB-powered device (say a smartphone or tablet) into the USB adapter to see if it causes any strange things to happen with your turn signals?

Are you using incandescent bulbs or LED type turn signal bulbs? If LED, what kind exactly?

 

[waylo]

Thanks for the ideas. I think I figured it out. I tested the situation just a bit more today, and did some googling as well.

I initially thought I must have somehow shorted something or blown a fuse, even though the install couldn't be simpler.

Yesterday I *thought* I could correlate the effect to having the USB connected to the dashcam (it's a Vantrue N1). Maybe it was just one fluke occurrence that made me think it was related.

Today, it occurred all the time whether the cam was connected or not. I re-opened the map light compartment to see if anything had come loose, but everything was still intact. (I took the opportunity to more securely wrap the connections in electrical tape).

As you had suggested, I turned on the hazard lights and interestingly the front left light did not illuminate! After some googling, it turns out this rapid blinker effect can be a 'warning signal' that the bulb is out or failing! Certainly feels like the bulb has failed now.

So maybe it is just a very untimely coincidence that this happened.

I'll replace it and report back.