[Android Head-Units] kaween:
That's an Szsion device. While running on the same Cedric cpu board, it has its very specific, non-AN21-design related problems.

There's a thread about these devices running on XDA about these devices, most of them are used in more upper-market cars like BMW's, Audi's and Volvo's.

Look here for more help : http://xdaforums.com/android/general/szsion-dual-core-a9-android-4-2-t2806857

---------- Post added at 11:54 PM ---------- Previous post was at 11:36 PM ----------

Euh, that's about as clear as mud to me. :) Bear with me : I've played with wireless reverse cams (and I'm GLAD I did away with them, nothing beats a physical cable when it comes to image quality, especially when the camera has to deal with low-light circumstances).

But I'll try to help you :

1) you say you connected the wireless receiver to "rear camera". Well, if that's the only thing you did, that is not enough for most 2din units, and that's also true for the AN21. You Unit will not automatically switch to reverse cam when video is passed through that line : it will only "switch to reverse" when the "reverse" control line of your headunit receives 12V when it has to activate the Reverse Cam video input, and it will swith to reverse mode NO_MATTER_IF_THERE's_A_VIDEO_SIGNAL_THERE. Which is my main problem with these "wireless solutions" : all nice and well to transmit your image wihtout having to pull a cable from the reverse cam to your headunit, but you WILL need to tell your headunit it has "to look at revers", and to do that, you STILL need to pull a cable from your reverse light to the headunit in order to let the unit detect you've put your car in reverse as the reverse light goes on. There's NO BYPASSING that. So that more or less defeats the purpose of the wireless interface if you still have to pull a cable to get that 12V Reverse-Detect to your headunit ..... ;)

In short : you will need to connect a cable from your reverse light to the "reverse" line of you headunit, so that the headunit receives 12V when the reverse light goes on : then, and only then will the headunit switch to "reverse cam" view. All headunits I've installed in my life so far work this way. A very small minority has the reverse cam under software control (and all of those I know of were WinCE type devices) which allowed "reverse view without the reverse control line".

2) A OBD BT module can only be used with the AN21 if the AN21-U you have is equipped with a BT board that can cope with "other stuff than just phones". MOST AN21's will be delivered with the so-called BC5 BT board, and this board _can_not_be_used_ for OBD BT communication unless you use a very specific OBD interface (name escapes me) and this module does NOT work with Torque. Using a Torque+lowcost OBD BT can only be done when your AN21 has a BC6 BT board. This board CAN be retrofitted when you have some basic electronic skills, but it does mean you'd have to open your head unit, desolder the existing BT board, replacing it with a BC6 version and modify your MCU to learn to work with it.

MOST people will find it easier to either buy a USB-based OBD interface (also cheap, but you'll have a USB cable running between OBD interface and your headunit) or buying a AP-capable Wifi-Based OBD interface. MOST Wifi OBD boards are pure ADHOC devices, which can NOT be used in this manner as they require an ADHOC communication setup between OBD and Headunit, and ADHOC is more or less "broken" on Android since ..... 2.1 I think ?

Be advised that USB OBD will only work on full, recent versions of Torque. If you need more info on the WIFI versions let me know, I'll dig it up again if need be.