Gentex backup camera monitor with pre-wired harness

[dajester]

I am attempting to install a Gentex rear view mirror in my '08 DC to display the video signal from the Toyota backup camera installed in the tailgate latch. The vehicle came prewired for the backup camera system, so I am attempting to use that as much as possible.

Of course the mirror's connector does not match the stock connector found behind the overhead console box, but equipped with the pinout information for both the mirror as well as the factory harness, it shouldn't be too difficult to match it up. Unfortunately, this is where I am falling short, I have been able to get power to the mirror, but no monitor display has come up yet.

Has anyone done this same installation before and could lend some experience? My apoligies if this same discussion has taken place already, but after hours of searching the net I've turned up very little useful information.

[deluxx]

Did you put your truck in reverse?

[dajester]

Yes, I did try putting the truck into reverse. Doing so has allowed me to locate a pin on the factory harness which provides a 14V signal when in reverse and off whenever not in reverse, but I do not know how the mirror would use this signal. Like I've said, the mirror itself has power, yet the monitor inside the mirror has not come on. Does the monitor require a separate power input from the rest of the mirror? Will the monitor only power on when it receives a signal from the camera? Which pins on the factory harness are the ones that relay the camera signal, and which pins on the mirror adapter are the ones that accept it?

[sageone]

I thought the Toyota Factory camera used something closer to 7vdc. I also thought that the power supply for the camera was actually incorporated into the Factory Monitor, no? This might be your problem.

[dajester]

I believe you are right about the voltage required for the camera. On the 4 wire vehicle harness in the tailgate that leads to the camera itself, I checked the voltage across what I believe were the CB+ (US2) and CGND (US3) pins and got a reading of about 6.5V. I would assume that this would be the power supply for the camera, and that the video signal would then be transmitted over the CV+ (US4) and CV- (US5) pins. I've gotten what would appear to be a pin diagram for the factory harness, which shows the CV+ and CV- pins on it, however there is never a voltage drop across these two pins in reverse or any other gear. On the other hand, I do not know if video signals normally have a noticeable voltage drop.

I've connected the pin that provides the 14V when in reverse to the pin on the monitor labeled as the Backup Trigger. Whenever I put the truck into reverse, the power indicator on the mirror flashes on and off. I am led to believe that this may be happening because the mirror is not getting a proper video signal, but I am unsure. Any thoughts?

[dajester]

Update:

I managed to get a video display up on the mirror, unfortunately it wasn't the one coming from the tailgate camera. After running an RCA cable out from the house into the car, the display came up properly on the mirror. The problem now seems to be getting a video signal from the camera. There are only 4 cables running to the camera, 2 are for power and 2 should be for the video. I know the harness in the tailgate is supplying a 6.5V signal to the camera, but I can't tell if the camera is operational. Anybody have any ideas on how to test this?

[pedro66]

If you dont have a stock NAV or Toyota monitor then you have no supply to the camera as either of these items is what converts the 12VDC from the truck to the camera 7VDC.

You will need to make/buy a power supply and connect it to the reverse signal to power the camera.

[dajester]

Ok, managed to get it working, and for future reference, here's how it works. Coming from the mirror adapter that gets run through the headliner, there are 7 wires which need to be connected. The factory harness running from the camera had 9 wires, even though the pin diagram I found on the Toyota TIS site only listed 8. All 7 wires from the camera do get connected to wires from the factory harness, which leaves 2 left over.

As I said, only 8 wires were shown on the pin diagram, I still have no idea what the 9th wire is for, as it seems to always provide a +14V drop when measured against a ground. The pins on the factory harness are as follows:

(The numbers in parenthesis are the pin number as it applies to an integrated circuit)

#4S: CGND (10)
#4U: CV- (9)
#4T: CV+ (8)
#4R: CB+ (7)
#4Z: GND (1)
#4X: REV (3)
#4Y: DIM (4)
#4W: ACC (5)

The afforementioned unknown wire was running into pin number 6, which I did not use for anything, neither was the DIM pin.

The camera adapter cable had 2 connectors on the opposite side of the cable plugged into the camera, a 4 pin connector and a 3 pin connector. The 4 pin connector had 2 sets of black and red wires running into it, the three pin connector had yellow, white and violet wires. Also running out of the mirror cable were two wires labeled OEC+ and OEC- which are apparantly used to control dimming side view mirrors, which I do not have.

Starting off with the cables in the three pin connector, the violet cable is what determines if the car is in the reverse gear. Plugging this wire into the REV pin on the factory harness provides the correct signal. The yellow wire should be connected to the CV+ pin, and the white wire should be plugged into the CV- pin. These two wires compromise the video signal coming from the camera.

On the 4 pin connector, hang with me as this may get kind of confusing, we have two pairs of red and black wires. On the extension cable that came with the mirror, the 4 pin connector that plugged into this only had 2 wires running into it, a black and a red. The 2 wires directly opposite this on the mirror harness are the power cables for the mirror. The red cable gets plugged into the ACC pin, and the black cable gets plugged into the GND pin. Now the mirror should have power, we need to provide power to the backup camera. The other set of red and black wires will provide the camera with a suitable power signal. Of these 2 wires, the red gets plugged into the CB+ pin and the black plugged into the CGND pin. These two wires should have a voltage drop across them of around 6-7V.

Once all these wires were connected as described, the monitor on the mirror displays whenever the truck is placed in reverse. On top of this, the camera is only powered whenever the truck is in reverse.

Should anyone have any questions about this installation or this post, please let me know and I'll help in any way I can.

[pedro66]

So is your new mirror providing the 7v

[slwdwn]

I'm interested it the same set up..How much did it cost you?

[dajester]

Yes, the mirror does provide the 7V signal for the camera power. The input power to the mirror comes from the ACC and GND pins. The mirror then outputs the 7V signal on a separate pair of red/black wires which get plugged into the CB+ and CGND pins, providing the camera with power.

The camera came from TRD Sparks and is listed at $162 (I don't remember how much shipping was). This included the camera, the cable to plug into the pre-wired harness, clips to keep the cable neatly tucked away, and a replacement tailgate latch designed for use with the camera.

I got the Gentex 3.5" display mirror off ebay for about $360 including shipping, which includes all the cables you'd need to wire this up.

Other than this, all you need for the installation are a T30 Torx bit for the tailgate disassembly/reassembly and a T20 Torx bit for the removal of the old mirror and disassembly/reassembly of the overhead console. A pair of wire cutters and a wire stripper would have come in handy, but I made do with a simple jackknife.

The installation of the camera took all of 10 minutes, as everything sent by TRD Sparks was a perfect fit and had good instructions. The instructions that came with the camera were not as thorough as the ones offered on the TRD Sparks site, so I would suggest downloading and printing those. The mirror installation, as you can probably tell from the above posts, was somewhat more difficult, but knowing what I know now, could probably get it done in about an hour or so.

[tomhole]

Thanks for a great post. Based on the info provided here, I ordered the camera from Sparks and the mirror from somewhere else. Looking at the wires, it looks like I can provide some clarity on the 2 red and black wires coming from the mirror.

The red/black wire is for ACC and the Black/white wire is for GND. This matches up with the adaptor harness that goes to the vehicle. The solid red is for CB+ and the solid black is for CGND. At least that's what I think it is. After I install it this weekend I will let you know for sure.

Is there a handy dandy part that I can attach to the ends of the wires coming from the mirror so that I can just plug them into the factory plug? I would like to keep the factory harness clean for now and just solder plugs onto the ends of the mirror wires and plug them in.

Thanks,

Tom

[SOSHeloPilot]

.
A friend of mine was having this same problem 2 weeks ago and put the project on hold until his unattached garage warms up a bit.

I called him and he was elated with this find.

Thanks for taking the time to post your progress and solutions.

SOS
.

[tun dra]

Thanks for the great post !

[tomhole]

Did this install today. Followed the pinouts as posted and it works like a champ. Thanks to the OP for a most excellent life saver.

I did add one feature that I wanted for towing. I put in a DPDT switch so that I could have the camera always on. Or it works just in reverse. This is so when I'm towing I can always have the camera on the back of the trailer displayed. Took a couple of pics.





If they won't display, here's a link to them:

2008_tundra Photo Gallery by Tom Hole at pbase.com

Now I have to add a relay to switch between the two cameras. Plan to put the relay at the back of the truck, tapping into the factory camera connection. The switch will go in the cab somewhere.

Tom