Android Nexus Tablet Install in 2007 Audi TT
I recently finished the install of a nexus 7 tablet into the dash of my 2007 Audit tt (MK2). I found a ton of helpful information online, but surprisingly all previous installs that I found were using the 2012 version of the Nexus 7, so I wanted to contribute back with how I hopefully improved on the install method of similar installs as well as using the latest 2013 version of the Nexus 7.
Overall Project Goals
- Total cost must be lower than standard double-din units
- Tablet must be able to come out with minimal effort
- Not alter permanently anything on the car - Must be able to go back to stock.
- Tablet must turn on/off with the vehicle
- Have full access to tablet while still in the Dash
- Ability to still use the steering wheel controls
- Ability to use Bluetooth or Aux for the radio
- Quality of Install must match quality of car - No Hack Jobs!
Parts Ordered for Install
- 2013 Nexus 7 Tablet - $229
- Scosche Vwa4B Audi/BMW/VW Antenna Adapter - $7.63
- Scosche Radio Wiring Harness for 2002-Up Volkswagen Power/Speaker Connector - $11.79
- Screen Protector / Anti-Glare for Nexus 7 - $8
- Micro USB OTG cable - $8
- USB Car Charger - $9
- USB Extension - $4
- USB Hub - $8
- Aux Cable - $3
- JVC Receiver - $86
- Steering Wheel Controll Interface - $45
- USB Audio Interface - $30 **Bought but not used
- Double Din Facia - $50 **Bought 2 in case something didn't go as planned with the first version
Total Cost of Parts used: ~$460
Configuring the Tablet
I found out far too late in my install that I couldn't use Timur's rom on the new nexus 7. The primary benefits of Timur's rom are:
- USB Host + Charging
- 'Fixed' install support for turning tablet on when outside power is received, and going to deep sleep when it's lost.
- USB Audio
The best solution that I found was: ElementalX - This enabled USB Fast Charging as well as the Host+Charging functionality.
With further searching and a rooted device I was able to get Android Tasker +Secure Settings turning off the tablet when power was lost as well as controlling the behavior when the tablet was turned on (turning on settings, launching apps,etc).
The most important Part of the setup to allow this all to work I found in this thread: http://forum.xda-dev...d.php?t=2496079
"fastboot oem-off-mode charge 0"
Timur's ROM takes care of auto-booting the tablet itself, but stock android behavior boots into a splash screen vs. straight into android when it receives charge from a full power loss state. The above setting enables the same behavior in a rooted device.
With the above ROM, Setting + Apps, I now had the tablet:
- Turning on the moment power was connected
- Launching / adjusting the tablet at each boot
- Turning itself off the moment the tablet would lose power*
I've played with various configurations for trying to mimic a 'deep sleep' by turning off all services, closing apps,etc,etc but so far nothing has managed to allow the tablet to hold enough charge to make it feasible. (Timur's rom has a more elegant way of accomplishing this)
Tasker is very powerful, and I'm still playing with the options, but for now I have two profiles setup, one that runs when external power is received, and the other that runs when the power is lost.
eg. of how everything comes together *Note - It's not like this in final
Tablet with OTG Cable * Note how wide the OTG cable comes straight out.
Pulling out the stock radio
Steering wheel + antenna connection, and Car-Lighter - USB connected to same power source as radio
Install Deck and bring USB extension + AUX cables into the glove box
Dremmel backside of the double-din so tablet will mount flush & Re-face front of double-din to match the exact size we want (vs. using the extension which then leaves a much less polished final product), Sand, Paint.
Mount the Tablet to the back of the fascia using silicone, OTG Cable needed to be modified/bent to allow for clean mount on side.
Total Project Cost
- Parts: $460
- Wiring / Plastic Work: $220
- Value of Time Spent: Don't Ask
- Total: $660
Things yet to complete
Play more with tasker to control tablet behavior based on Time of day and Battery. eg:
- Don't launch with max brightness when it's night time
- Don't immediately shutdown the tablet - eg. I'm just getting gas and don't want it to power completely off for those 5 mins
- If Battery is over X then don't shutdown immediately
Things I would do differently
- Configure more of the tablet prior to installing it into the car. I found out hours before I was mounting the tablet that Timur's ROM didn't support the 2013 Nexus
- ROM support for USB audio - Although the Bluetooth audio quality is more than acceptable*
- Purchase a tablet with data - I'm currently just running a hot-spot from my phone when I want data
- User a higher quality receiver for rear AUX input and more control over the stock car amp
- More robust internal power connection; Skip the car lighter to USB
- Fit the opening to leave more gap room at the bottom edge of the screen so that the actions are easier to touch there.
Tasker has difference profiles that run at:
- Remote Power On - Turn tablet on / init settings
- Remote Power Off - Turn Tablet off
- Screen unlock - Start apps + I found that volume setting wouldn't work on 'power on' profile, so moved it here
- Time of day - I have two profiles to adjust the brightness automatically on time of day, i.e. bright during day, dim at night.
- *Some of this uses 'secure settings' as a plugin.
Only things really that I've left to experiment with:
- Make it so it doesn't automatically shut-off when loss of power, eg. I'm getting gas and don't want it to turn off completely (probably just dim/turn-off screen so that if I am parking my car at night it's still not shining bright when no one is in it)
- Auto-play the music - It starts the music player, but having it auto-play on start would be a nice-to-have.