The Treehouse Blog

The generic double-DIN Android head unit I purchased is a TH8581GA.  Sometimes branded as an Ouku, the unit appears to be a close cousin to the Ca-Fi 621000.

Specs

Notes and observations

Bluetooth:  The radio does have built-in Bluetooth, but it is not managed by Android.  Pairing with the radio allows for interacting with the Phone application on the radio (handsfree), as well as passing through A2DP audio.  However, it is not possible to use the built-in Bluetooth for pairing with other devices through Android, such as a OBDII bridge.

Booting:  The radio takes about 40 seconds from power-on to Android, another 10 seconds before the internal and external storage is mounted, and in my case, about 10 more seconds for the on-boot apps to finish loading.  The radio does not appear to have much of a concept of sleep – when power is removed, the radio is off and requires a reboot.  I have noticed in my install that if I power off the vehicle and immediately put it into accessory mode, the radio display will go dark, and come back in several seconds without a reboot.  I’m not sure of the exact scenario, but I suspect this is more of my vehicle maintaining accessory power for a short while, as opposed to the radio sleeping.

Sensors:  I’m used to android devices (e.g., phones) being loaded with an excessive number of awesome sensors, such as compasses, accelerometers, orientation, etc.  Unfortunately, this device does not have any of that.  So much for having an artificial horizon in my car.  It does, however, have an integrated GPS receiver with external antenna (provided).

Other Info:  Internal Pictures

Coming up soon… Installation.

Background

While shopping for my 2011 Toyota RAV4, I tried out vehicles that both had and did not have the factory navigation package. I decided that I basically didn’t like it. The one I purchased did not have the navigation package, but did have the “JBL” audio package and Bluetooth hands-free support, which seemed to work well.  After having some annoyance in mounting my aging Garmin nuvi (and having it stick properly), problems with the factory radio sometimes not working, and probably some pent up desire for a “project”, I embarked on finding a alternative.

Alternatives

I gave up on any cellphone-only solution since I needed to replace the factory radio anyway, and did not wanted a solution that appeared integrated (e.g., did not involve something with a windshield or bean-bag mount).

One set of options are the new head units that tether to your cell phone, allowing you to control your cell phone through the in-dash unit.  These generally involve HDMI output from your phone and use a Bluetooth connection for communicating touch screen interactions.  An example is the AppRadio series from Pioneer.  In researching this, it appears that the functionality is somewhat crippled out of the box, and that with a 3rd party app (ARLiberator).  I do think this notion has promise (and it did finally push me over the edge to buying the Slimport to HDMI adapter that works with my Nexus 4), but if I had to plug in my phone for each use, it mostly would be left undone except for extended trips.  This just did not seem to be the right answer.

The next option was a head unit that natively runs Android.  There brand name in this field seems to be Ca-Fi.  There are a number of knock-offs of this brand, the most common of which is being actively discussed on xda-developers.  I chose to get one of these units, and I will detail that adventure in upcoming articles.