BACK UP CAMERA FOR 2012 PRIUS two TOUCH SCREEN- NON NAV

Congrats; from the time stamp on your msg, you must have worked into the night. Happy to see you went for the roof connection. It really is the cleanest way.

Dan.

 

[Update] Last Sunday, I looked around a larger parking space around my apt and I brought my car over there and work afternoon. It was successful. I installed a relay circuit that ray6088 suggested. Taking parts and panels was the most time consuming steps. Especially, if it is the first time! Be careful not to take out the rubber from the plastic hole(frame) connecting between rear door and body upper. I route wire from the rubber to the rear left trunk and then go to left door. The video I posted was helpful. Esp., I don't have to remove a strip of plastic panel in the rear door outside to mount camera. I used a stripper to peel off PVC in the middle of wire (4 in the driver panel+1 in rear wiper) and soldered to avoid power loss. BTW, I used 18AWG wire which is little thicker.

 

Nelsc,
It sounded like you pulled the headliner off. Was there any trick to doing that ? Did you just pull the 3 white plugs
near the back or did you have to unhook something by the overhead light ? Thanks

 

While I'm waiting for my prius to hit 36K , I thought I would take a look at two of the backup cameras that people are using. Since I'm going the 3.3V regulator route, I was looking at 3.3V cameras. Two that I found were from chenwenjiaoeb09 and cardvd2010. The chen camera came in a padded envelope. The cardvd camera came in a box in a padded envelope. While they both have the same specs, they seem to be constructed a little different . The chen camera seems to be in a plastic tub to protect it. The cardvd camera is more out in the open. Both say they are waterproof. I'm not sure which way is better, because if any water gets in and the tub starts filling up, the camera is going to drown . There is no way for water to get trapped in the cardvd camera, but it is more exposed to the elements. Both cameras have the snaps to fit the cutout in the Prius hatch. There also seems to be a difference in their picture quality. The chen camera seems to have a wider field of view compared to the cardvd camera. Again I don't know which way is better since you are interested in what is behind you and not way off to the side. The chen picture seems to be a little brighter, but I don't know if that is because of the difference in viewing angle. The real test is how long they last on the car. Another unknown is how often they change suppliers. What they send you today, may not be what they send you a year from now. I'm not sure what one to put in my car so comments/suggestions are welcomed.

 

I had to pull a lot of things off. It was a lot of trouble but I was bored at work one night and decided to tackle it. I do have some knowledge at car trim but it's been a while so I have to go slow and figure it out as I go. Back to the point, I had to remove the lower back trim so I could remove the trim around the two small back windows, and then remove the rubber around the back doors (where it overlaps the headliner) also the plugs in the back that holds the liner up then removed the dome light and rear grab handles. That gave me all the room I needed. Then I used solid wires to push into the blank spots in the plug (that would match up to the factory wires on the opposite plug). then ran my wires to the camera. You really need the plastic trim tools to make it easier so you damage the trim. It was a lot of work and probably not worth it. But hey I was working nights with little going on so what the heck, I got paid to go through all the trouble.

I would run it to the kick panel if I wasn't getting paid for it.(LOL) Way easier!!!
I would have taken pictures but it was hictic doing it between things at work. I would work on it 3 minutes one time then maybe an hour the next?
Good luck its not bad if you follow everyones learnings in here.
Dan4500 was a hugh help to me!!!

 

Nelsc,
Thanks for the update. I keep bouncing back and forth between the headliner and the kick panel route. That is a neat trick about pushing the solid wire in the connector. Saves having to go to the dealer and get some connector pins.

 

I unplugged mine and the pin connectors were in it, so I push the solid wire in the empty slot and they locked in perfect. I tested the first one by trying to pull it back out and I couldn’t get it out. (It was locked in place) after that I hooked up a meter to check them and had 6V on power and conductivity on the others.

 

Nelsc,
The pin connectors were already in the socket ? That was very nice of Toyota to do that. You have to wonder how much more it would have cost them to put the camera in the car to begin with (a camera and 4 wires). You don't happen to know what gauge wire you used do you ? Thanks

 

On my car (2013 Prius two)

IF VIDEO SIGNAL IS NOT SENT TO HU:
Upon startup the 6V wire goes to 6V and then a few seconds later goes to 0V, and stays that way.

IF VIDEO SIGNAL IS SENT TO HU:
Upon startup the 6V wire goes to 6V and stays that way. It does not go to 0V at any time.
This happens even if the 6V wire is not used (e.g. camera hooked up directly to blue 12V wire for power)

Based on this behavior, if you are using that 6V line to determine when to turn on the camera, the camera will simply stay on when the car is on. You could get the same effect by not bothering with the 6V line, a relay, or modifying the voltage regulator... just hook up the camera power to the blue 12V wire, then hook up the 2 video wires.

Questions:
1 - Is it a problem to keep the camera on the whole time the car is on?
2 - I wonder if the stock Prius camera behaves this way?
3 - Perhaps I've done something wrong with my wiring... can someone else test their 6V line for constant voltage after the car starts?

 

I checked my headliner plug, there were no pins in mine on the female side
Perhaps Nelsc's wires were jammed in against the male end of the plug, and held there by friction?

 

Wes_33073,
Having the camera on all the time is not a good thing. I'm sure it has a finite life, and running it anytime the car is on will make it not last as long. I can't believe the stock camera would be set up this way. I thought the 6V would only be sent when the car was placed in Reverse and turned off when it was taken out of Reverse (after the power up sensing is done). Wes_33073, what method were you going to use (ie relay, regulator, etc) ?
I think we need Dan4500 to do his magic again

 

I have everything set up to use a relay. I tried a 12VDC relay I had laying around, but of course it wouldn't trigger the coil... the 6VDC relay should be here tomorrow.

Many thanks to everyone on the forums here to get us this far, of course including Dan4500 and Willco Electronics!

It would be nice if someone who has a factory-installed camera could check their 6V line, but not holding my breath... after all, why would they be reading this?!?

 

Wes_33073,
A question. If I read all these forum entries correctly there are two ways the HU knows about the camera. One, it can sense the video signal on the Red wire. Two, it can sense the return voltage on the orange wire. In your test setup are you using the red wire or the orange wire ? LanLam in append #177 just hitched up the video signal to the red wire, connected the camera to a 12V source (blue wire) and everything worked.
The HU may act differently if it sees the return voltage on the orange wire. I know Dan4500 figured out that the orange wire was more than just a ground for the 6V white wire.
While we wait for Wes to get back with info on his setup, a little speculation. I wonder if the HU does the following, or I hope it does the following
1) Puts 6V on the white wire . 2) Checks for a Video Signal on the Red wire. 3) If no Video Signal, no camera is attached, turn off 6V. 4) If Video Signal is present check orange wire for return voltage. 5) If no return voltage, camera is getting power from somewhere else, so leave 6V on (shouldn't matter since no one is using it). 6) If there is return voltage, HU knows it is controlling power to camera, so turn on 6V when car is put in Reverse.
The one thing that is strange is Dan4500 said the orange wire is really thin compared to the other wires. I wonder why that is ??

 

Starting off, I don't intend to offend anyone, but in reading the prior posts, I think some of the "successful" installs result in the need for work arounds at power up, may be to supplemental displays, and/or continuous displays, whether on the HU or a supplemental display. I bought my first Prius in Sep 2012 and am a relative newby to Prius Chat. I goofed when signing up as a Three owner. I have a Two b/c I did not want to spend the $ for the GPS with its expensive updates. But I did want the backup cam. I joined this thread at about page 8 and have sifted through all pages and some several times. My solution is on page 10 and forward. Following is compilation of my contribution:

1. Get the set of Trim removal tools from Harbor Freight to remove the panels. On sale they are about $7. Well worth it. Make sure you don't lose any of the snap in fasteners. I broke the pins holding the back of the headliner, cost $2.00 each at the dealer to replace.
2. Make sure to pull the rubber strip out and over the external plastic trim strip across the back hatch when you replace it. This keeps rain from getting in behind it and messing up the installation and other Toyota stuff behind it. I used masking tape. There's another poster who used either grass trimmer line or heavy fishing line.
3. Use silicone lube (from a pool, home depot or auto supply store) to get the wires through the left rubber tube thingy. Silicone lube is more inert than petroleum lube and will not rot the tube or other wires. The tube is made of silicone rubber.
4. Willco planned to post the timing of the 6 volts and the video signals, etc. but never got around to it. I measured the sequences with a voltmeter and reported them somewhere around pages 8-10. When power button is pressed, 6 volts appears on the white wire. If a camera is present, the current from the 6 volts returns by flowing back into the orange wire, signaling the head unit to look for video on the red wire, with the black wire being the return for the video. The HU performs this inquiry and detection process in 3-4 seconds while the Toyota logo is displayed. If the 6 volt current doesn't show up returning on the ORG wire and/or the video doesn't show up on the red wire, the HU says no Backup Cam is present.
5. I did research the diode configuration and discovered its roots derived from postings in one of the Prius C forums. After some study, I could not figure how the posted circuit would work. Somewhere along the way, the diodes got reversed in the subsequently posted diagrams. I eventually studied the original diode circuit posting and determined that it could work if the operating parameters of the selected camera were within a certain envelop. Thus I could understand the reports of success with the diodes. I reported this also somewhere around pages 8-10.
6. As a EE, I dislike using relays so hence came up with the circuit on page 10. Relays, being mechanical do fail, although very infreqently. Solid state is more reliable. Additionally, a relay introduces another variable: the coil current, which depends on the size of the relay. Willco and I agree on the HU activation current levels being in the range of 150 milliamps. Some relays could draw this same amount of current. The solid state circuit uses only a miniscule amount of current beyond that of the camera's requirement. The relay coil current could affect detection or operation.
7. Thusly, what Willco did was to create a 6 volt camera (from a 12 volt) that works like the factory Toyota camera. His postings are on pages 12-14. Why they used a 6 volt camera is inexplicable unless the HU manufacturer forced it or Toyota just wanted to be obnoxious. Willco used surface mount techniques to modify his 12 volt camera which requires super eyesight and fine detail hand dexterity. Plus miniature tools. He went for the roof connection which is about as "factory install" as you can get. I congratulate Willco for his modification and installation.
8. My circuit posted on page 10 makes the 12 volt camera emulate a 6 volt camera. Thus it looks like a factory camera to the HU. I gave nelsc an alternate for the PNP transistor as the 2n2907. The MPS is harder to find. The transistors and resistors total less than a buck if you have electronics store close. The circuit board was another buck, but really is not necessary as you can use a plastic margarine tub lid to mount the components. (Use an ice pick to punch holes for the wires and leads.) I covered the board with plastic electrical tape (make sure no wires can contact the hatch metal) and wire tied it to the cable bundle in the hatch lid. Harbor Freight has a soldering kit including solder for about $12. Plenty of clearance behind the inside trim piece.
9. I ran the video cable and 2 other conducters to the driver kick panel. The camera came with a video cable (yellow RCA plugs, each end) with a third red conductor (wire lead ends). Rather than cutting the RCA plugs off, I added a female RCA jack at the kick panel to the red and black wires. Connected the red conductor to the white wire to carry the 6 volts back to the circuit and I added an additional long wire (stranded 22 guage) to connect the ORG wire to the emitter of the 2n2222.
10. Last, connect the 12volt (2n2907 emitter (arrowhead) to the lt Blue wire at the rear wiper motor. It's always hot ( ON) so be careful not to have any tools like the solder iron connected to the Prius chassis. To be absolutely safe, disconnect the 12 volt battery or remove the fuse for the wiper.
11. Reconnect, reassemble, and enjoy. Make sure to pull the rubber strip back over to trim piece. It's easy to forget this and just put the trim piece over the rubber. If you break the headliner pins, they are $2.00 at Toyota dealer.
12. I decided to use the 4 connections as Toyota intended. Some have reported success with three wires. But I recall the comment "so what if its on all the time". It may be possible to share the video return with the power return, but I did not want to risk too far from the emulation. Also the reports of being always "ON" suggest that the battery may be draining continuously. The wiper connect point is always ON. Both Willco and my circuit are OFF with Power down since they are controlled by the 6 volt line. The relay also should cut everything off.
13. Using the relay may be okay, but it's additional current draw takes it out of a close emulation of the factory camera. As described earlier, both Willco's and my installs look just like a factory camera to the HU.
14. Rather than reposting diagrams and photos , I refer you all to page 8 and onward of this thread. I'm almost to the point of wanting to turn the camera On to catch the tailgaters when stopped at a red light. Too bad the Prius ICE turns off so I can't get em to suck my exhaust.
Again, I do not want this posting to be taken as a rant. I intend only to clarify why I (and Willco) did what we did. This is a great resource and the Prius has been an extremely satisfying purchase. For those who followed this thread closely, we did stop the legislation, and I'm still working on getting Torque (monitor app) running.

dan4500.

 

Dan4500,
I didn't mean to make you think that you needed to repost all your great work (but it does make it easier for the late arrivals to quickly catch up with what happened in the first 13 pages I just wondered in your setup if you happen to notice if the 6V got turned off when the car was taken out of Reverse. I just read your append again, and I change my question. I know the white wire will be off when the car is powered off, but would you expect it to be off if the car is not in Reverse ? Thanks

 

To our1vue:
It looks like we posted simultaneously. I need to explain the electrical concept of voltage and current. Voltage can be thought of as a measure of the difference in pressure between 2 points in a circuit. Think of a multi story building. If you now carry a tank of water with an attached faucet and hose and drag the tank with the attached end of the hose up the stairs, the increase in height will increase the pressure in the hose when you open the valve. This pressure is analogous to voltage. Each floor going up increases the pressure or voltage. The pressure then causes the water to run through the hose faster with more height of the tank. Electrical current is analogous to the water running through the hose.

Now in the case of the HU detection of the camera:
1. Think of the wires as hoses.
2. When you Power On the Prius, the 6.5 volt tank has been raised but no water/current flow occurs if there is NO camera connected. The valve is closed and water/current in the WHT wire cannot flow across the non-existent camera to the ORG wire to tell the HU that a camera is present. On the other hand if a camera or anything that will provide a path from WHT to ORG, then current will flow to tell the HU that something is connected. If no current, then HU says no camera and HU remains no cam operation.
3. Then HU looks for Video to identify what is letting current flow into ORG wire. If Video is coming in, HU sets a flag or internal indicator that camera is present. HU drops the 6.5 volts and relaxes. This all occurs during the logo display. If no Video then HU says something is trying to fool me, cuts the process off. It's a 2 stage check.
4. Now with the detect flag set, when you shift into reverse, HU turns on the 6.5 to activate camera and when Video comes in it will switch the display to the backup camera.
5. This process sort of explains why some report success with shifting to reverse when starting up. (A work around)

YOU DO NOT WANT TO PUT 6.5 VOLTS OR ANY OTHER VOLTAGE DIRECTLY ON THE ORG WIRE. IT IS CURRENT THAT GOES INTO IT AND THAT CURRENT NEEDS TO BE IN A CERTAIN RANGE. And from a source at a higher voltage , BUT CONTROLLED. Willco and I think that it is in the range of 100-300 milliamps. That's what we designed our circuits to do. Using a relay could drastically increase the current, depending on the circuit and the relay type. PUTTING ANY VOLTAGE ON THE ORG WIRE MAY NOT BE HEALTHY. Putting a voltage directly on ORG is no limit to the amount of current. It's been clear to me that current is the activating stimulus for the ORG wire. It's also why I call it "RETURN" because it's used to return all the camera current back to the HU and not to chassis (ground). It will eventually get there but after going through the HU detection circuitry. Still don't know why it is thinner.

Finally a disclaimer that all this is with my 2012 Prius Two bought in Sept 2012. HU has 6.1 inch diag display.

dan4500.

 

The answer is in the second post. HU turns off the 6.5 volts after detecting cam/no-cam Then if cam turns on when put in reverse, it gets turned on during time in reverse.

I guess I'm celebrating the stopping of the legislation I mentioned in an earlier posting. Deadlines passed this week.

Actually find PriusChat to be quite useful as well as entertaining. Been thinking for a while about tying things together here.

 

Dan4500,
Thanks for the explanation. Being a compsi this is all magic to me. I tried to follow your example by calling the orange wire a "voltage return" instead of a ground in my append. One thing, I thought you weren't suppose to mix electricity with water
As a side note I got a 2012 prius 2 because I didn't want the NAV package too. I've also been pretty happy with the radio reception (AM and FM) . I wonder if NAV/XM radio has worse reception to make you want to keep your XM subscription ?

 

I never activated XM. Don't spend enough time in the Prius to justify, even though it seems to have all the necessities of living on a set of wheels. My favorite FM station is 100 miles away. It even works to about 150 miles.

What do you mean: Don't mix water with electricity. Haven't you ever tried Jolt with bourbon or rum? (Not in the Prius; that don't compute.