Video input to MFD

television camera ECU

Looks like the Television Camera ECU on the Lexus RX330
has wiring diagrams that look promising for use in the 2004
Prius with Nav. That ECU sits between the Nav unit
RGBS video output and the MultiDisplay RGBS input.
Depending on the state of the reverse signal it either
passes the nav video through or switches to a converted
version of the camera input. The NAV ECU connector has
the same pinout on the connector leading to the MultiDisplay.
That plus the existance of the camera test option on the
Prius maintenance screen are hints of possible compatibility.

So I went to the local Lexus dealer to see if I could order it.
I was expecting something like $60 to $100 based on the vaguely
similar 08635-28020 shown at
http://www17.tok2.com/home/rinapapa/es78.html and
http://userwww.aimnet.ne.jp/user/sa-sa-ki/...Back%20mon5.htm

With a straight face, the parts guy told me the part# was 86792-48050
and the price was $1817.32+tax! Unbelievable. If anyone has
a Lexus RX330 and is willing to loan out the TVCam ECU,
I'll be glad to try it in my Prius and post the results!

Seems like one would need to unplug N3 (10 pins) on the Prius
Nav ECU and build a cable harness that conects the middle (T16)
connector on the TVCamECU to both N3 and its mate
on various pins. Then you'd need to apply video on pins
30 and 29 of T18 (the left) of the TVCamECU. And finally
connect power,ground and reverse signals to pins
2,6,11 respectively of T17 (on the right) of the TVCamECU.
That plus $1817.

My reading of the wiring of the cheaper 08635-28020 is that
it would probably generate signals which drive the MultiDisplay,
but couldn't auto-switch between video and camera. An external
A/B 4PDT switch could solve that. So far I can't find a way to
buy it in the US and hear it's actually pretty tough to buy
such parts in Japan unless you own a vehicle the part is
intended for.

 

Re: Video input to MFD - working!

I've finally got video on the MultiDisplay. Been trying many alternatives in the background in recent months, but now have hit upon one which will work. Still have a bit of work to do with switching sources, clean connectors and mounting things but the proof-of-concept shot is attached below.

For now I just positioned the camera over the back seat and popped the hatch so I'd have some sort of view out the back. Of course while everything's loose, you can point the camera at the display and get one of those picture-in-picture-in-picture... amusement shots (2nd attachment).

So what I've got is a cheap monochrome security camera that runs on 12V (about $40) plus the Toyota 08635-28020 NTSC to RGBS converter featured at this site: http://www17.tok2.com/home/rinapapa/es78.html which has a lot of good wiring detail (but for another car). The converter is only available in Japan and costs about $60. A friend with connections in Tokyo got one for me. I've unplugged the RGBS connector from the nav unit and temporarily hooked it up to the converter. So whenever I select MAP, MENU or DEST on the display, it shows the camera input. Later I'll tap into the Reverse signal and built an electronic A-B video switch. Hopefully I'll be able to find both the plug and socket for the NAV connector to avoid cutting wires for the final install. So far only found one end (by cutting the $15 cable 08635-0010 also featured in the above site).
Anyone have any sources for the mating 10 pin connector?

 

It looks like a solution may already be here, for a fee:


http://www.mobilevideo4less.com/Merchant2/...Code=NAV-V300TY

Nate

 

I've been emailing back and forth with this vendor to find out more about this. Their price for the unit alone is $599 (+$10 UPS shipping). In the email he quoted $800 saying I'd have to send him the head unit for installation and test. Trying to find out if this is required. The specs look good and the installation doesn't seem any harder than what we've already done here. What does everyone think?

 

Seems like a lot of money, but certainly if you go for it let us know where it connects into the system, what connector are used, etc. Although a delta of $200 seems like a lot, if that gets you most of the installation and a guarantee of success and eliminated wire-cutting for you,it could be worth it. The base price on the other hand seems kind of high. You might want to look at the price of some of the add-on systems which include a display & TV tuner to help judge.

 

Brosnan, I'm gathering from your post that the key to doing it yourself is getting that Japanese connector. Is it safe to say that if we found a source for more of those, that we could come up with a lower cost solution?

This has been asked before with respect to the OEM EV button, but does anyone have a Japanese connector to order more of these?

Brosnan, how much did it cost you and can you get more?

 

Getting both the plug and socket of the 10 pin connector would allow us to do this without cutting wires in the car. However, it will still require building a small electronic box to do the A/B switching and soldering the components inside that. The 08635-00010 cable's connector cost about $15 in Japan. I'm not sure if the mating version is for sale but I'll look for it while in Japan in a couple weeks.

Even if we can't track down a source for the connector, it's possible to do this by cutting the video cable going to the Nav ECU and splicing onto each end.

If we can arrange to source all the needed parts, I'd say the total materials cost for a B/W backup camera addition would end up in the $200 range when using cheap security camera modules and the B/W 08635-28020 converter. For those wanting a camera module that fits nicely in the license plate frame area, that might require another $600 to get the Toyota 86790-28090. Then there's a range in between for aftermarket cameras intended for car use.

 

Sounds like a plan may be coming together. Obviously, if you're going to Japan yourself, then you have the opportunity to buy a few more of these parts, assuming they're stocked. Definitely count me in for one. As for the video connections themselves, the vendor I talked with just splices them in directly without a connector.

I do like their idea of having the aux video support two external sources, one for the backup camera and the other for a video player. The user manually switches to aux video mode, and their box switches between the camera and player depending upon the Reverse direction input.

The only other consideration is what video format to support. I'd assume since the basic market for this is US, that it would be NTSC. To support Europe, we'd have to convert to PAL.

 

OK, now what about an European Prius II without Navi... Is there any chance to have a camera working on that one?
Of course there is no need then for a switch between Navi- and Camera-pictures, but... is there any video input at all in a Prius without Navi???

Richard W. Born

 

Re: Video input to MFD instructions

Here's a fairly detailed writeup of what I've done to get B&W video from a backup camera, TV, DVD and MP3 onto the MFD. I don't really expect anyone's really going to want to follow all these instructions, but hopefully some parts will be helpful to those trying to add some video features.

Since I can't squeeze it down under 1MByte, I've got a link to another site where you can find the instructions in zipped PDF format: http://home.comcast.net/~brosnan1/backupcam.zip

I've also got a bigger file with higher resolution pictures - send me a message if you want the oversized version.

 

I researched through google for NTSC to RGB or NTSC to VGA converters. Came across several links:

http://www.starkelectronic.com/vga300.htm
http://elm-chan.org/works/sc/report.html
http://elm-chan.org/works/yuv2rgb/report.html
http://www.converters.tv/products/converte...erters/139.html
http://www.twobits.com/VIDEO2RGB/
http://www.highway.net.au/parts/converters/2020.html
http://www.ramelectronics.net/html/video-v...a-gvm-2000.html

Found cheaper listing for GVM-2000 at
http://www.legallydigital.com/gtec/gt_avpr...prods22103.html

 

DanMan32,
Thanks - I'll have to track down one of these converters and see if it drives the Prius display properly. Color sure would be nice.

 

If the Prius' native input is RGB, can you hook up a stantdard VGA cable to it? I ask because it would be great to get the full resolution out of the MFD.

 

I've been meaning to try that as I alreadt have the break out box. Most likely if I set my laptop VGA video output resolution low enough and to interlaced mode and get the right RGB,Sync wires connected, it should work. Eventually I'll try it and post the results. Seems I saw a very old web link where someone has done this with a Prius display and a linux machine.

 

Anybody know what the VR (Video Return) line is for?

 

Video return is essentially a ground wire dedicated specifically to the video signals.

 

Well I came close to getting PC video on the MFD. Built an adapter from DB15 to the NAV/MFD video cable. Obviously the red,green and blue channels were connected from the DB15 to the similar MFD video channels. The DB15 connector has H Sync and V Sync signals so I chose to connect "H Sync" to the MFD sync line. I used a Sony laptop and set it to 640x480 60Hz.

The photo below shows that it sort of works, but the picture shifted and duplicated. I think what's happening is that I coudn't really get interlaced video from the laptop. There certainly were no inherent settings for this. So I tried powermill, which does have a checkbox to select Interlaced. But I'm skeptical it did anything. The picture looked the same for either setting. Maybe the Rage Mobility video chip used in the Sony doesn't support interlaced.

Next step is to figure out how to get known 60Hz interlaced signals from a PC.

 

Not sure if the actual resolution of the MFD is 640x480. See if you can use 512x384 or 320x240 (which I suspect is the most likely resolution). Non-interlaced.

You're making me very excited! Keep up the good work!

 

Don't know if this would help, but try coupling the H sync and the V Sync from the VGA with a .1uF capacitor from each to the MFD Sync line.

And about resolution, another thread mentioned that the display was 800x480. A demo of Coastal's soon to come out unit has the picture stretched horizontally so that would make sense.

I don't think putting a non-interlaced signal into a display requireing interlace to cause a horizontal doubling.

Time to buy some alligator clips...