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

Discussion in 'Gen 3 Prius Accessories and Modifications' started by man2ing, Jul 4, 2012.

  1. priusbee

    priusbee Member

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    If you read the previous posts, the camera is already has a regulator inside of it. Either a 6 or 12 volt line for the camera video + line is okay. Since the camera already has that capability, adding a solenoid will not be needed.
     
  2. Dan4500

    Dan4500 Junior Member

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    Am an EE so I have been proceeding slowly and in experimental steps. When I first got the camera, I connected it to a Lab power supply and a small video display and determined its operating supply voltage range to be 7 to 12+ volts. Below 7 it gets fuzzy and goes dark at 6 volts. This weekend, I've hooked the camera up to the footwell connector with the 4 connections. Used clipleads. I measured the voltage on Orange (gnd) & White (6) volts and upon pushing the Power startup button, the voltage jumps to 6.3 for about 2-3 seconds, then drops to zero. Never comes back up even when put into reverse. Display unit never switches to camera. Priusbee, your theory that the headunit detects the camera certainly seems to make sense, but my Prius sure doesn't seem to work that way.

    So the theory that the headunit tests for presence of camera may not be valid. Anyone got more info on this? I have also tried a dummy resisitive load (100mA) on Orange & White which does not trigger the head unit. So does the relay actually work? I have planned to rig up a transistor to turn on the 12 volt camera, but it certainly doesn't work with a resistive load. Does it need to be inductive (the relay coil?). But then a 6 volt camera would be resisitive. I don't really understand all the earlier talk about diodes.

    Can we get a post from someone who has succesfully connected a camera to the headunit? And has it working automatically upon reverse

    My Prius is a late 2012. Did they change the headunit operation? I'm sure that I used the correct pins in the footwell connector Orange & White for power; Red & Black for camera plus & minus. The Red & Black clearly are the video. They work on both the small video display and a big flat screen TV that I have tested it on.

    I'm almost ready to give-in and just hook up the small display using the back-up lamp voltage. Not elegant but sure to work. And I can put the car back together.
     
    our1vue likes this.
  3. our1vue

    our1vue Member

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    Dan4500,
    Great post, but I don't like what you are seeing :) I'm not an EE (was a programmer, so me and hardware have issues at times) I talked to an EE and he suggested the resistor. For the value of it he was going to measure the resistance of the camera. I wonder if your resistor is resistive enough. Is your prius a North American unit ? What model prius do you have ? I thought the 2012 prius 3 had the navigation/backup camera. A scary thought is
    that they put a stop to adding the camera by making it a dealer only selectable option. I know GM did this with
    cruise control on some of their cars.
     
  4. priusbee

    priusbee Member

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    Okay, it looks like the regulator in your camera will not take the 6 volt. So, we have to scrap that idea using the 6-volt line.

    According to the previous posts, the best alternative solution is to use a 6-volt relay, which drives the 12 volt which feed the 12 volt camera. During the Prius software boot-up sequence, it checks the 6-volt line. Having the 6-volt relay connected, it tell the Prius system that the camera is available.

    P.S. I thought that Prius III already have backup camera installed?
     
  5. PriusTime

    PriusTime Junior Member

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    He is not using the same camera I am. Stop jumping to conclusions.
     
  6. Dan4500

    Dan4500 Junior Member

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    Wow, is this an active blog. Firstly I have a Two. When I signed up I made an erroneous selection and don't know how to correct it.

    It's true that I may have a different camera. But it's got the bulge where the cables are molded together. I have not taken it apart. It sure looks like the photos of the other referenced cameras. But the voltage testing on it is as I have reported. Dies at just above 6 volts. Does not trigger the head unit.

    The resistor loads I used were 50 & 125 mA. Neither triggerred the head unit.

    For the EE techies, I did an out of car lab circuit mockup of my transistor circuit and it does work with 6 volts driving the base of the NPN transistor with the collector switching the camera to ground. It's a 2N2222 family transistor with the appropriate resistors to regulate the base current. Essentially a solid state relay; cheaper and more reliable than the relay. I would post the circuit but since I cannot get my head unit to work with anything, I hesitate to add to the confusion.

    I have done additional web searching and apparently sometime in mid-late 2012, Toyota changed the model of the head unit. There are dealers who sell head units who caution that the early 2012 Prius uses a 2011 head unit & later it became a 2012.

    Its begining to look like an additional display. The one I have will fit into the space under the big Power button. Will be out of the way but still usable, visible thru the steering wheel.
     
  7. ray6088

    ray6088 Junior Member

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    Oh well, I'm not saying you're wrong, but not many people like to open the sealed camera and modify it. Please consider the most of us, the "average joe". We are not having strong electrical background as you are.
     
  8. priusbee

    priusbee Member

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    Can you diagram your circuitry describe above, draw it on a canvas? I am curious.
    You may not even bother since you can also buy a solid state relay for a few dollars.
    There is more than one way of doing this, for most people the easier the better.
     
  9. PaJa

    PaJa Senior member

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    Dan 4500:
    As I read, the solenoid solution works for some owners (ray6088 | PriusChat), so let's try it and you will see if OEM HU will detect the camera. Will be good to post the picture of HU's manufacturer label. It can be compared after that with Ray. The circuit diagram can be found at http://priuschat.com/attachments/camera2-png.42170/
     
  10. our1vue

    our1vue Member

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    Do you have to pull the HU to see the manufacture label ? Could we do a quick look at the car manufacture date to see if the early HU or the later HU are the ones that work ?
     
  11. Dan4500

    Dan4500 Junior Member

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    DumLong & Ray:
    Could you each tell us the configuration you have used? Relay, no-relay, 12 volt camera, 6 volt camera, etc. Wired into kick panel or where? Also what your head unit looks like: what the working buttons on it are labeled. I have (CD up-pointer; seek; track; audio) -on left & (CD-skip; setup; car; phone) -on right. There are an additional 2 or 4 dummy buttons or space fillers. What the numbers on your head unit bezel are. (Mine is 57031). Display screen measures 6 inches diag.

    Does it work acording to expectations? Auto switch to backup cam and back when shifting to reverse?

    Thanks. Just knowing someone has it working helps.
     
  12. ray6088

    ray6088 Junior Member

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    Please read post #28 carefully! Rephrase it! Please please read post #28 post #28 carefully!!
    If those four wires exist on the kicker panel, you're ready to install by "T" those 4 wires.
    Since there are a lot perfectly fit camera for 2012 prius in eBay, but they are 12v. Therefore the relay is required! It's much harder to find 6v camera or cost too much.
    Let's me say it again "revisit post #28 again!#
     
  13. Dan4500

    Dan4500 Junior Member

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    Okay I can finally report success. Thanks, Ray for pointing out post 28. I have the 12 volt camera working as it is supposed to and with transistor(s) instead of relay. I am posting the circuit here. But first would like to share some info that may be helpful.

    I went to an aftermarket car audio installer. He looked up 2012 Prius on his data base and it said any 6.5 and 7.0 inch display HU can display the BU camera. My unit measures 6.1 inches, but I figured the display is rated bigger, like 6.5 inches, the way TV sets are rated. So I figured I would give it a go myself since he wanted $300 matl plus $120 labor to put one in. Thanked him for the info and left. So this is where those $300 cameras we see on eBay are from.

    Got adventurous and took out my HU. Its a Panasonic Model 86140-47050, Ref No. CDV-VS01E64D. There's a terrific Service Guide on www.toyota-tech.eu titled "Rear View Camera" (manual Reference No. AIM 001 911-1). Its for a 2009, but very useful to show how to pry off trim pieces, and disassemble. Radio as well as the body and hatch trim pieces.

    I found that a little silicone lube works wonders to get the cable through the rubber tunnel thingy between the roof and the hatch. This the stuff used by swimming pool service guys to keep the gaskets on the equipment moveable but yet watertight. Since the tunnel thingy is silicone rubber, it's very compatible.

    And don't forget to use masking tape or cord to pull the rubber back up over the plastic trim piece on the hatch.

    Okay, now for the circuit, (no moving parts):

    I used an opto isolator (NTE 3041) to drive a transistor (2n2222 or ss8050, NPN, handles 500mA). The opto can handle 100 mA. I did not want to push it. The NTE 3041 and 2n2222 are from Frys and also available on Ebay. Total cost about $3.00. I built the circuit on a PC board from Radio Shack. It was $3.00 for 2 boards, about 1.5 inches square. It does make for a neater package that I mounted on the inside of the hatch by wire tying it to a cable bundle. The 2 resistors can be either 1.8K or 2.4K. I just happened to have one of each handy. Probably could be much broader range but I just picked the values as being sure to work.

    After putting this together and doing some testing, I think I have figured out that:

    1. They use the return line (orange) to sense the current that a camera is attached. The 6.5 line (white) is used to poke the camera on Power-up to get a response on the return line. But there is no need to load the 6.5 line as my circuit only takes about 3.5mA from it.
    2. When the 6.5 line turns on the camera, the 12 volt current (nearly 100mA) runs through it into the return line, signaling that a camera is there.
    3. The opto isolator works like a relay, but no moving parts and uses less current.
    4. I was very happy and suprised that the 6.5 line needed no dummy load.

    My camera came with an 18 foot video cable and a separate single wire (essentially 3 conductors). I used the wire to carry the 6.5 volt switching signal and added an additional single 4th wire to run the return line to the camera circuit. The video cable has RCA plugs at both ends. I kept the RCA plugs and plugged one end into the camera. Wired a female RCA to the kick panel connector red and black and just plugged the other end in. Wired the 2 single wires to white and orange at the kick panel.

    For pulling wires/cables, I found that the 4 "strand" indoor telphone cable is very useful. Its made from solid 26 guage wire which holds its configuration so can be pushed a distance. It's what I used to pull through the tunnel thingy.

    After messing with the headliner a bit, I have to agree that its too much of a PIA. Bad enough, I had to pull the cable through the tunnel thingy.

    Camera works like a champ. Thanks all who came before.
     

    Attached Files:

  14. our1vue

    our1vue Member

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    Dan4500,
    Glad the "new" radios still work. I have no idea, what your diagram says, but I know someone who can translate it for me :) One question. If we put in the OEM 6V camera, and the 6V is supplied on the white wire, wouldn't that put 6V (or what ever is let through the camera) on the orange wire ? It looks like your circuit is putting 12V (or again what is let through the camera) on the orange wire. Again I'm not an EE so this may be a stupid question. Thanks again for the circuit diagram.
     
  15. Dan4500

    Dan4500 Junior Member

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    My circuit is for a 12 volt camera to be used on the 6 volt Prius. The camera current from the 12 volts runs through the camera and then into into the orange wire. If you have a 6 volt camera, you don't need my circuit. However, I have yet to see a cheap 6 volt camera on Ebay. There are a bunch of 12 volt cameras on Ebay that will click/clip into the Prius camera slot. I think the 6 volt cameras are the ones that run $300. This circuit plus a 12 volt camera can be had for $30-35.
     
  16. Dan4500

    Dan4500 Junior Member

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    Be very careful with the Orange wire. It's alot softer & thinner than the other 3. It also has a double jacket insulation at the footwell connector.
     
  17. LanIam

    LanIam Junior Member

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    I had a sucessful camera install over the weekend.

    Car: 2012 Prius 2, Non-Nav, Mfg. Date 3/12

    Camera: SONY CCD CAR REAR VIEW REVERSE CAMERA FOR TOYOTA PRIUS 2012
    Sony CCD Car Rear View Reverse Camera for Toyota Prius 2012 | eBay
    Connections: Video + to Red wire , Video - to black wire, (red & black shown in the taped wire bundle at the drivers kick panel of post #27), 12vdc Camera power wire to blue wire in rear wiper motor connector.

    No relay or diodes needed, that is the only connections I made.

    If the red and black wires are cut in two at the connector, connect to the taped side for correct connection to the display.
    The pdf in post #78 was very helpful with interior panel removal along with some interior removal tools.
    For the hole through the rear hatch I used a 3/4 in. antenna hole saw and 3/4 in. antenna hole plug since the power and video connectors are pretty big.
     
  18. our1vue

    our1vue Member

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    Lanlam,
    Where did you connect the camera's ground, to the frame of the car or to the orange wire ? Also doesn't using the blue wiper power line leave the camera powered up all the time when the car is on ?
     
  19. Dan4500

    Dan4500 Junior Member

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    Just a FYI. I broke 2 of the 3 pins that hold up the rear of the headliner. No other fasteners lost or broken. The pins are available from the local Toyota dealer parts dept at $1.50 each.
     
  20. Dan4500

    Dan4500 Junior Member

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    Also get the trim pry tools kit from Harbor Freight. I got them on sale for about $6.00.