Obviously, this tutorial revolves around a specific vehicle series. However, I am writing this as a guide to anyone who is trying to accomplish the same in a different vehicle. Some of these steps are similar, and some of the problems you will encounter are the same.
So first we should talk a little about safety:
In doing this project you will have ample opportunity to do damage to yourself, your equipment, and your car. Use appropriate care when soldering, cutting plastic, and working with electrical wiring and circuits.
This mod allows you to install a fully functional tablet in your car where you can play with it while driving. Need I say this is a dangerous and distracting toy? While you will be able to play videos on this thing, trying to watch videos whilst in the driver's seat is just asking for trouble, so don't do it.
Also, you will want to mess with settings and such while driving. Don't do that either: you will be risking not only your own neck, but those of anyone else in the general area.
Step 1: Parts and Tools Required
So, the parts I obtained included the following:
- The installation kit for the car
- The tablet (a Galaxy Tab 2 7.0) with charging cable
- An extra μSD to SD cable (because the kit came with an SD to SD extender)
- A μSD adapter
- A dual-port USB car charger (2.4a per port, total 4.8a charging capability)
- An "Add a Circuit" kit
In the picture, you will also see a battery. This is a replacement battery for the tablet, as that was one of the reasons it was set aside/replaced for daily use and therefore free to be installed in the car.
For tools (not pictured, you should already know what they are) I used:
- A soldering iron
- A drill bit
- Socket set or hand driver with bit set
- Wire stripper
- Sharp bladed instrument
- Crimping tool (used for ring terminals and automotive splices; may be part of your wire stripper)
- Automotive body tool kit (plastic knives, interior panel removers)
Some consumables I used:
- Electrical wire
- Silicone RTV
- Electrical tape
Step 2: Prep Part 1-- Hardware
So, we need to prep our equipment.
For me, I had to change the battery on the tablet. I considered soldering in some small wires to be sent to external switches to replace the buttons I would no longer have access to, but I changed my mind because A) I found other, simpler solutions to the problem of no buttons; and B) I no longer had access to unlimited amounts of small wiring and (particularly important in the proposed operation) I didn't have a microscope and fancy solder station with which to work.
If you find you need your switches available, then know this: soldering on the inside of a tablet such as this requires intermediate to advanced soldering skills and good equipment. As an avionics technician, I had access to the aforementioned microscope and soldering equipment (and owned an awesome set of tools) before I changed jobs, so I had the tools and the talent to do so. If in doubt, then don't try it-- you'll end up breaking something.
Second thing: since my tablet had a light sensor, and I wanted to utilize the built-in automatic brightness feature, I had to drill a hole in the bezel of my tablet mount. The resulting hole (drilled using my fingers only and largish bit) is shown in the first picture. I used a piece of transparent tape on the tablet and a marker to identify where the sensor would need to be, then transferred that tape to the bezel. This required laying one edge of the tape along the edge of the display, identifying and then accurately marking the location of the sensor (bright light at an angle helps you to see through the darkened glass), and marking the borders of the screen itself (which I wanted centered in the opening). So, three markings in total, remove tape from tablet and transfer to the bezel, aligning the edge of the tape and those border markings, then drilling your hole over the mark where your sensor lay.
Third: getting the new extension cable in place. The kit came with an SD extension cable and, conveniently enough, an USB extension as well. They mount in the top of the new display enclosure. The extension cables press-fit into the plastic holder, but the new μSD to SD card cable had some inconvenient (for me) tabs on either side that had to come off. I scored the plastic and used a pair of pliers to break off the tabs, then filed them down until the new SD card receiver fit snugly into the plastic holder. I then glued both extension cables into the holder with judicious applications of a little RTV. I had pictures, but my phone lost them before I moved them to the computer. Go figure.
Fourth item: the USB charger. I wanted to be able to charge my tablet without wires hanging out all over the place; or for that matter, clogging up my power port, so I decided to wire in a dedicated charger for the tablet. As picture three shows, I broke the guts out of the plastic containment, then removed the spring and tangs. I soldered a wire in place of the positive spring, and a second wire to the common case of the USB socket. The wires I used were scavenged from a ceiling fan installation earlier in the week, which is why the blue and black instead of, say the traditional red and black. As long as you, the installer, know which wire is which, that's all that really matters-- no one should see your wiring after all is said and done. After soldering the wires on (and ensuring you have a good connection--tug those wires!) I wrapped some electrical tape around the entire assembly to protect it from shorting against anything.
Step 3: Prep 2: Software
The intent here is to replace the stock stereo options with something more flexible. An added bonus for me is the larger screen for navigation, when using my phone as a hot-spot.
Rant: Interfacing with the car
So, the 2014 Cruze LT has a crappy single-channel bluetooth input. This allows my phone to connect with the stereo system for hands-free calling, but not for media. Additionally, the stereo system did not connect well with Android via USB.
Sure, I could use a thumb-drive to move music to the stereo (and I do), but one of the annoyances was the fact that the stereo did not always read the metadata on the .mp3 files correctly (if at all), for no discernible reason.
There is an auxiliary jack, but again Chevy decided to go that extra mile and hobble it by using an amplifier optimized for voice only-- music sounds like lukewarm crap.
In my case, I found a solution: one can actually install an improved Power Data Interface Module (PDIM) from a Camaro which has two bluetooth transceivers. The first, of course for the phone, and a second for audio (see this thread). The audio input is still optimized for voice and not music, so I needn't worry about wiring in the headphone jack of the tablet (or tapping the audio outputs of the charging/data port).
I installed a debloated version of the stock Samsung firmware on the tablet (rooted). I loaded MediaMonkey Pro for my music manager, Google Maps for navigation, and Tasker.
Since I wouldn't have access to the power button on this tablet, I had to have a way of turning it on. With it rooted, I could use this solution to get the GT2 to power on when I turn the car on (the charger will be plugged into a switched power circuit).
I can use Tasker to put the phone into Airplane mode when the power is removed, thus saving battery. I can even set it to power the phone off after being idle for a certain amount of time.
One note on Tasker-- I am a novice with this software, and so I am learning as I go here. I have found that Tasker can only do things that the firmware on the tablet allows you to do. With Android 4.x, you can't just turn off the GPS/Location. Your screen-on time is limited to what your settings dialog allows, so where my tablet allows me to set max thirty minutes, that's what i have to have Tasker set (I got around this by going into Developer options and setting the screen to stay on when plugged into the charger).
I suggest setting up bluetooth, wifi (with your home network, your phone hotspot, if necessary) and such before mounting your tablet. It's just easier typing in passwords and such when not sitting in the car and leaning toward the center console.
For the Cruze, adding the tablet for bluetooth requires you to go to Aux Input, then hitting the settings button and choosing your bluetooth connection that way. You can have the tablet assigned BT for audio, and your phone for telephony stuff (under regular Setting menu).
Step 4: Prep 3: Mounting the Tablet
For the Galaxy Tab 2 7.0, the opening in the mounting fixture is only slightly larger than the viewable screen on the tablet itself. Also, the mounting posts on the fixture are a little too close for the table to just slide right in.
My solution was to cut away a portion of the posts with knife and round file, until I could slide the tablet into place and it would sit flush with the fixture.
Of course, I already had my peep hole drilled for the auto-brightness feature, and I tested that with the tablet in place to make sure that the hole was where it should be. Do everything you need to do before the next step, because this is pretty permanent. Test your SD card cable connection., test your power cord connection. I had to trim part of the locking tab on my fixture to accommodate the charging/data cable.
Next step-- glue your tablet in place with RTV. I carefully noted where I had to slide my tablet into the notches I made in those mounting posts, and placed a little RTV on the inner face of the fixture where the sliding wouldn't smear it to somewhere inconvenient. I placed the GT2 exactly where I wanted it to sit, then ran a thick bead of RTV around the perimeter between tablet and fixture and allowed this to cure for 24 hours before picking the assembly up and doing anything more with it.
Yes, you should be able to peel the RTV off the tablet if necessary, but from this point on, you don't want to need to.
Step 5: Install
For this install, I had to remove the silver vent assembly, using an interior panel tool.
Once removed, two 10mm screws hold the radio panel in place, then two more 10mm screws hold the stock display and holder in its place.
Unplug the display cable, remove the display from the holder, and install it into the new mount. The little popup tray on top of the dash comes out with two screws under the mat and the new display holder will snap into place (don't put it in yet!). There is nothing to keep you from plugging the display extender cable incorrectly, so make careful note of how the cable originally goes into the display and use the two white wires as a guide for plugging it in the right way (also, make sure you don't miss a row of pins).
Thread your USB and SD extender cables down into the space behind the center display area. The SD cable will plug into your tablet as it goes in. My replacement cable was barely long enough, so I had to install it into the tablet before I snapped the new display mount into place on top of the dash, so keep that in mind while working.
The USB extender had no real use to me for the tablet, though I can think of some things I could have done. For instance, I could have used a powered USB hub, thus being able to plug my computer into the tablet and updating my music on it that way, but the convenient SD card holder on top made that kind of redundant. So instead, I plugged the extension into the second USB socket of the charger, therefore giving a charging port right on top of the dash, a convenient location for my dash-mounted phone charger (or dashcam)!
I threaded the charger with its attached cables into the space below the left vent, and ran the power wire (mine was blue, remember) into the fusebox. Behind the center display area, there were two ground studs. I cut away some plastic so I could get a socket on one of those nuts, removed it, and put my black (Common) wire on there using a ring terminal.
I also had to remove a little plastic on the left side to accommodate my power/data cable connector, so the tablet is always connected while installed. Granted, no data is going through, but for that 2.4a charge, I need the data lines intact. Keep that in mind should your tablet use one of the newer μUSB connectors: if you have a (sub)standard charging cable with no data lines in it, your smart tablet will only pull 0.5a and you will likely kill your battery in short order. (always-on display plus BT will draw more current than can be delivered through slow charge).
With the tablet in place, I routed my charge cable around the vent, and spliced in my "Add a Circuit" adapter.
Now, I wanted to use a switched power source, so I wouldn't be draining my battery by charging the tablet while the car was off, plus the act of turning the vehicle on will power on said tablet. As it turns out, my power ports are switched power, and the fuses for them are right in center of the fusebox: Fuse 6 is the front power port, and fuse 7 is the rear one.
I decided to use the rarely used rear power port. You can get the "Add a Circuit" kit at most well-outfitted auto parts stores (such as the Pep Boys around the corner). These ones are rated for 10 amps. Considering that the power ports on this car are equipped with 20 amp fuses, I decided to use the more robust 20 amp "Add a Circuit" kit available through Amazon.com (note: the low-profile one will not work in the Chevy Cruze). Sure, I could have downgraded the fuse for the power port to be on the safe side, but if I ever decide to run an inverter or one of those portable air compressors, I'm going to need all the amperage I can get, so there is that.
Now, my dedicated power port is going to use at most 2 amps. The smallest fuse in my kit was 5 amps, so I went with that. This gives me a good amount of protection against a short-circuit, and will not blow out if I end up charging two high-current devices at the same time, though I may go with a 3a mini fuse later, when I make my next trip to the auto store.
The "Add a Circuit" has two fuse slots. The slot closest to the pins (where it plugs into the fusebox) is the original fuse location, and the other (the 'top' as it were) is protection for your new circuit.
Now is the time to test everything out--before you close everything up, make sure that the tablet powers up when you turn the key, the BT and wifi work, your stock display powers up and displays, your μSD card is being detected by the tablet through the extension cable, etc.
Once you are satisfied that all that is working, then you can put all the screws in, snap your top display into place and the trim.
Step 6: We Did It!
There you have it. An upgraded media station plus Navigation. The standard radio controls interface with the tablet via BT, as do the steering wheel controls. You still can have music or audiobooks on USB drive, but those are also very doable on the new tablet.
Additionally, the tablet is less likely to throw fits with a larger-sized SD card, unlike the Cruze stereo with even a 32GB USB drive, so there is that.
I hope this tutorial has been of help, even for people outfitting non-Cruze vehicles, and I will try to answer questions as they crop up.
Enjoy your upgrade!