The E46 BMW is a wonderful car, with an unfortunate lack of aftermarket "infotainment" opportunities due to the shape of the stock head unit. It's curvy and extra-wide, and most aftermarket head unit brackets end up looking really awful, like this:
Come on now, that looks horrible.
The other option is made by companies such as Dynavin. They produce a drop-in, 2-DIN unit that runs on Windows CE or Android 2.x, has a clunky interface, gives you iPod/Bluetooth/navigation, and is typically slow and very outdated with software that can't be upgraded. They do at least look physically nice:
So, when the other half decided that his 330i's stock head unit wasn't acceptable (he wanted aux input and Bluetooth), we both agreed that the "easy button" aftermarket upgrades were hardly upgrades due to the downsides.
Fortunately, the size of the dashboard lends itself to fitting a 7" tablet. The iPad Mini doesn't work very well as the screen is the wrong aspect ratio, and iOS is not flexible enough to be customized sufficiently for in-car use. The Nexus 7 is the easiest option. And, to make it even better, there's a guy who custom-makes bezels for the E46 (and other BMWs) that are sized to accommodate a 7" tablet, mounting brackets and all.
We are not the first people to put a Nexus 7 in a car, but I think we certainly did one of the cleaner installs. A lot of folks will hide the stock head unit (or an aftermarket, if stock doesn't have Aux in) and route the audio through the head unit to the speakers. Well, why do that? BMW head units do not amplify the audio. Rather, there's an amp in the trunk with front and rear inputs. So, this install was pretty easy.
First, you gotta remove some things.
The climate control panel can be relocated to where the "sunglasses holder" pocket is, in front of the shifter. Some E46's came with factory Navigation, so their climate panels were down there by default. That means you can order the BMW bracket to hold the panel. Unfortunately, he was shipped the wrong bracket, so his climate panel is just kinda pushed in there until ECS Tuning can re-send the correct bracket.
From there, you have to figure out your wiring "flow" to make sure things are in order. We elected to use a USB digital audio converter (DAC) as it's a cleaner output than the Nexus's headphone jack. From there, we routed the DAC's output to a Clarion EQ that is mounted in the glovebox. This provides equalization abilities that are accessible, and also conveniently splits the one sound output from the DAC into a Front/Rear set of outputs.
The Front/Rear outputs are routed directly to the BMW/Harman Kardon amp in the trunk. My roommate and I soldered RCA connectors directly to the proper wiring coming from the BMW radio harness behind the dash. The amp and EQ both require a "trigger wire" to make them turn on with the ignition. You can tap those directly to the red 12V power wire of the BMW radio harness.
Sorry I didn't take more photos of the install, I forgot entirely and three of us were all busy getting this done.
Anyway, here's the layout of how this all works:
You make sure it all functions before you solder, then you solder, heatshrink, and reinstall everything. We stuck the DAC and EQ and hub to various inside-the-dash support bits using Velcro strips.
Finished product! It uses a custom ROM to allow for charging + external USB devices. The ROM also makes the device turn on and off when power is supplied (aka, with ignition key). The launch screen is a combination of custom wallpaper, a "desktop widgetizer" app to create landing zones that launch the apps, and UCCW widgets for all the info on the left sidebar.
Internet access is required for this whole shebang to work, so his phone creates a WiFi network (he has an unlimited LTE data plan) that the tablet connects to when the car is started.
Come on now, that looks horrible.
The other option is made by companies such as Dynavin. They produce a drop-in, 2-DIN unit that runs on Windows CE or Android 2.x, has a clunky interface, gives you iPod/Bluetooth/navigation, and is typically slow and very outdated with software that can't be upgraded. They do at least look physically nice:
So, when the other half decided that his 330i's stock head unit wasn't acceptable (he wanted aux input and Bluetooth), we both agreed that the "easy button" aftermarket upgrades were hardly upgrades due to the downsides.
Fortunately, the size of the dashboard lends itself to fitting a 7" tablet. The iPad Mini doesn't work very well as the screen is the wrong aspect ratio, and iOS is not flexible enough to be customized sufficiently for in-car use. The Nexus 7 is the easiest option. And, to make it even better, there's a guy who custom-makes bezels for the E46 (and other BMWs) that are sized to accommodate a 7" tablet, mounting brackets and all.
We are not the first people to put a Nexus 7 in a car, but I think we certainly did one of the cleaner installs. A lot of folks will hide the stock head unit (or an aftermarket, if stock doesn't have Aux in) and route the audio through the head unit to the speakers. Well, why do that? BMW head units do not amplify the audio. Rather, there's an amp in the trunk with front and rear inputs. So, this install was pretty easy.
First, you gotta remove some things.
The climate control panel can be relocated to where the "sunglasses holder" pocket is, in front of the shifter. Some E46's came with factory Navigation, so their climate panels were down there by default. That means you can order the BMW bracket to hold the panel. Unfortunately, he was shipped the wrong bracket, so his climate panel is just kinda pushed in there until ECS Tuning can re-send the correct bracket.
From there, you have to figure out your wiring "flow" to make sure things are in order. We elected to use a USB digital audio converter (DAC) as it's a cleaner output than the Nexus's headphone jack. From there, we routed the DAC's output to a Clarion EQ that is mounted in the glovebox. This provides equalization abilities that are accessible, and also conveniently splits the one sound output from the DAC into a Front/Rear set of outputs.
The Front/Rear outputs are routed directly to the BMW/Harman Kardon amp in the trunk. My roommate and I soldered RCA connectors directly to the proper wiring coming from the BMW radio harness behind the dash. The amp and EQ both require a "trigger wire" to make them turn on with the ignition. You can tap those directly to the red 12V power wire of the BMW radio harness.
Sorry I didn't take more photos of the install, I forgot entirely and three of us were all busy getting this done.
Anyway, here's the layout of how this all works:
You make sure it all functions before you solder, then you solder, heatshrink, and reinstall everything. We stuck the DAC and EQ and hub to various inside-the-dash support bits using Velcro strips.
Finished product! It uses a custom ROM to allow for charging + external USB devices. The ROM also makes the device turn on and off when power is supplied (aka, with ignition key). The launch screen is a combination of custom wallpaper, a "desktop widgetizer" app to create landing zones that launch the apps, and UCCW widgets for all the info on the left sidebar.
Internet access is required for this whole shebang to work, so his phone creates a WiFi network (he has an unlimited LTE data plan) that the tablet connects to when the car is started.