90% of the work for the head unit install is in the harness. Given the number of harnesses out there for our car, it can (and should) be done out of the car. I wish I would have bought my harness off of ae64.com, as opposed to the generic metra harness. The generic metra harness is missing a few pins that are required for the steering wheel controls as well as the parking brake bypass. I believe the metra harness is missing one other signal - maybe the headlight/dimmer signal.
The harness came out fairly well.
If you haven't constructed a radio harness before, the black plug on the left comes with the head unit. It'll have several color coated wires that match up (hopefully) to your factory radio harness. It's recommended that you leave your factory harness in tact, and get an 'extension' harness. This will allow you to simply disconnect the entire harness from the factory unit, and plug your new head unit in - no soldering/splicing required to the factory wiring.
Few general tips to making it nice and cleanly:
- Get shrink wrap and have a hair dryer handy. Don't forget to put it on BEFORE soldering the joint (we've all done it)
- Solder everything up pretty nicely. Some tips for those that aren't 'solder friendly':
- Keep a wet sponge nearby. Use this to clean the soldering iron once the iron is hot
- Tin the soldering iron with just a dab of solder. The liquid solder is more heat conductive than the clean soldering iron.
- Important part most people miss - Heat up BOTH materials you wish to solder together. Push the soldering iron onto the joint of both wires, wait a few seconds to heat both wires up to the appropriate temp...
- Feed a rather small amount of solder into the place where your iron contacts the wires. The wires should "wick" the hot solder right up. Don't overdo it. If the solder beads off, you didn't get the materials heated up. Try again.
- Wipe the soldering iron off with the sponge afterwards, or continue to do the other joints you have laid out
- Start with your speaker wires (assuming you are re-using factory wiring and using the head unit amps). This will get you started and get the harness set up a bit. The color codes match up for the most part as well (check out ae64.com for the color codes). After you have finished with them, bundle them up neatly with a few wire ties to sorta form one "cable" to keep things neat.
- Work through the other wires one by one. Take special note of any 3 (or 4) way solder joints you'll need. You are on your own for those... they suck and being a bit OCD... I hate them. Apply shrink wrap over the end of any wires you don't use to avoid shorts to ground. Fold over any longer wires after soldering/shrink wrapping and zip tie them as well. Try to keep them all about the same length and to form one "cable".
- Some special wires and explanations (ae64.com will help ya out here as well)
- Illumination wire: Most aftermarket head units don't use an analog 'dimmer'. They use the headlight signal (digital... on/off) to apply either a "bright" or "dim" setting. Should be a one to one joint here and pretty straight forward.
- Remote power: This is a big wire, especially if you are amping your system. If you have a glass mounted antenna (subarus do), they use this as an "antenna booster". Basically, the antenna requires a small amount of power to amplify its reception. Luckily this is low amperage and safe to use the remote power signal for. If its an older car with a motorized antenna, that may be pushing it. This may require multiple tie offs... Your head unit will output it and several things will use it including your amps, antenna, and parking brake bypass. DON'T USE THIS AS YOUR STANDARD POWER WIRE... I've personally ignited this wire by accident. Thin wires and large amperage do not mix well
- Accessory power: This is on when the ignition is on 'accessory mode'. I think of it as a signal wire so the head unit knows when to turn on. Don't use this as your standard power either... It'd get annoying to reset your clock and presets every time you turn your car on. I believe this guy has a few things coming off of it as well.
- Constant power: This is the guy you want. He supplies enough current (bulkier wire actually) for the head unit to do its thing.
- Ground: Yup, Subaru includes a ground in their harness for the head unit. I used it. It's one of the few brands that do. Most just tie to the head unit body.
- Steering wheel controls: I used ae64.com's guidance on these guys. I'd suggest you do the same.
- Reverse signal: Found a post on iwsti. I grabbed a brown wire with a yellow stripe from the passenger kick panel. This is an input to the head unit & rear cam that gives a 12V signal when the car is in reverse.
- Just be persistent and take your time. It's worth it to not have to hack the factory harness apart and use those stupid quick connects that always become quick-disconnects. I'd suggest avoiding "vampire taps" where possible. I cheated and used one to get the reverse signal. Who knows if it'll work long term or not.
Actual head unit install is pretty simple:
- Remove ground lead from battery for safety sake - Yours and the electronics
- Pull dash bezel around head unit
- Pull head unit
- Wire up accessories as needed (mic/gps/hdmi/etc)
- Put in new head unit
- Put bezel back
- Plug battery back in
...Really fairly easy. I had my doubts, but the head unit portion is pretty clean cut. The dash panel is pretty easy to remove for these cars. I'll attach some pictures of the process.
I don't have one of actually removing the bezel - I'd look on youtube. Basically, wedge a thin screw driver or trim tool in the lower left or right of the panel (along that 45 degree bend part) and push and wiggle until it pops a clip loose. Then pull from the vent area and it should come out without too much fuss.
Another one to show the location of where that clip is at. There are clips along the bottom of the bezel, and push pins along the top and sides:
Vent piece removed. Jamming the steering wheel control module back there:
As far as accessories for this unit:
- GPS Receiver: I did this at a later time with the amp install. I basically reached up to the left of the clock and stuck it on top of a vent duct under the defroster. It works well and isn't sitting on top of the dash board. As long as its level and not hidden behind metal, you should be okay. Its crazy how much faster it is to pick up the signal than the standard internal phone GPS.
- iPhone/iPod Hookup: I just snaked it through an opening to the passenger glove box. It sits in there with my iPod hooked up 24/7. Works and is out of the way.
- Microphone: I snaked the cable out towards the pedals actually, and then back up and stuck the mic on top of the steering column facing me. It's kinda an eye sore, but it picks up my voice pretty well and people can actually hear me. Oh the wonders of actually pointing the mic at your mouth.
- HDMI: I managed to get this thing out in the little cubby under the head unit (with the cigarette lighter). I have a car charger plugged in there which supplies power to the MHL adapter. The phone plugs into the MHL adapter and sits in that cubby hole nicely
...Sub & Amp install to come shortly!