Our recently acquired SLK55 came with the base Audio 20 stereo. It did AM/FM, played single CDs, and sounded pretty crummy doing it. No iPod integration either. "This will not stand", we both declared. And the search was on. After dealing with several local installers (either folks I wouldn't trust to park my car, let along put a stereo in it, or were unwilling to listen to what I wanted, and tried to sell me what they wanted to sell), I decided to do it myself.
We picked out the Alpine W505 because we have (and have had) other Alpines, and they've been great. In addition, the W505 will dock a Blackbird II navigation unit, which we intend to add to the system, as soon as the budget recovers.
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| Alpine W505 unboxed |
The unit comes with:
For installation in an SLK you will not need the trim ring or sleeve. Nor the AV extension cable - no back seats!
I ordered the following additional items from other suppliers:
List of part numbers and suppliers
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| Other parts |
A word about the Video ByPass Unit (TR-7). By law multimedia capable units must disable video functions for the front seat screens while the vehicle is in motion. So if you want to watch a movie while you're sitting on the ferry you have to have some way of "proving" to the unit that you are parked. This is done by performing the "dance of foot brake and parking brake" which the unit senses. In the SLK these signals are routed through the CAN-BUS. The Alpine unit does not have native CAN-BUS support. In order to get these signals into the unit you need a CAN-BUS adapter. And you'd still be stuck with a system that wouldn't allow video while moving. Not good enough.
So why, you ask, do I want video while I'm driving. I don't. But there are a number of function of the blackbird GPS/Nav that are disabled while the vehicle is in motion. Including most of the routing functions. If you usually drive two up it's very handy for the co-pilot/navigator to be able to operate all of the Nav functions while in flight.
That said there are options for generating the appropriate signals and passing them to the unit. The TR-7 it is a general purpose signal sequencer, and can be programmed to generate signals to control any number of devices such amplifiers, antennas, actuators, etc. These are often used in complicated or show-car audio installations. In this installation, it’s only job is to fool the Alpine deck into thinking the parking brake/foot brake dance has been performed. Luckily the PAC TR-7 comes pre-programmed for this sequence, all I had to do is hook it up. NOTE: it’s probably illegal to install the deck this way, probably illegal to have video in view of the driver, and certainly a bad idea to whip down the freeway watching “Independence Day.” Don’t do it.
I also gathered some tools:
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| Before Picture showing the stock Audio 20 unit | ."
To start with, I put the roof down, figuring it would decrease the number of times I clobbered my noggin on things.
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| Shifter boot/face plate removed |
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| Switch panel removed from lower console (and the ashtray which you'll take out in the next step. |
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| Ashtray removed. |
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| Removing the heater control panel |
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| Disconnecting heater control wiring |
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| Removing the OEM unit |
So now it was time to explore exactly how the unit was going to fit in the car, and all that. So I attached the Scosche mount kit faceplate to the W505, and held it up to the gaping hole in our car. (expletive!) As you can see in photos, the Scosche faceplate is about 6mm wider than the OEM unit, and consequently, than the hole in the console.
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| test fit of the Scoche faceplate |
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| Difference in width |
Many phone calls later, Car Audio Design in Everett, WA came to my rescue. They got me a Metra install kit in a couple of hours. They also got me the antenna adapter that I had discovered I needed. If you are in the Puget Sound area of the NW US, I recommend them highly.
Note that the web page is in Spanish but the staff speaks English as well.
OK, now it’s time to figure out how to wire this puppy up. I sat down with the harness that came with the Alpine unit, the harness I bought from Blue Spot (whose primary contribution was a plug to fit into the factory harness in the SLK), and the PAC TR-7 controller/sequencer.
Both the Blue Spot and the Alpine connectors use the ISO standard colors for the wiring. If you're careful when you cut the ISO connector off of the Blue Spot Harness you'll have plenty of wire to make the soldering not too onerous.
Now I had to solve the ACC issue. There is no switched power in the M-B (car side) connector. I got switched ACC by tapping into the cigarette lighter power wire. I did this using a 3M scotchlock tap and a short piece of wire with a bullet connector. Later I would attach both the power for the TR-7 and the power for the head to this.
Hooking up the TR-7 was easy following their instructions.
It will all look vaguely like this very ugly wiring diagram. If you can draw a better one please let me know.
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| Wiring Diagram |
Get it all wired up, with everything heat-shrinked and all, but not bundled up yet, in case I had to make changes.
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| Hooked up |
Yay! Only problem in first smoke test was that I wasn’t paying enough attention to where the fm/am antenna connector was supposed to go. The Alpine has both a pigtail and a similar looking jack in the back of the chassis. Helpful hint: it’s the pigtail. Not sure what the jack is for, I could look it up if I needed to know.
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| Smoke test |
Now to get the unit and all the cabling in the car.
First task is to get the iPod and USB cables into the glove box. There is a pre-cut whole in the back of the glove box, just about the right size for an iPod dock connector. Coincidence? I don’t think so! The photo shows the glove box, with the hole punched out and the iPod connector from the Alpine fed through
For the USB connector, I had a bit of trouble, the USB end was a just a little too big to fit through the slot in the glove box. I thought about enlarging the hole, but then I noticed that the end of the connector that plugged into the Alpine was a smaller, and would fit through the hole just fine if I removed the factory noise choke temporarily. Fed the connector through, put the choke back on, and I had my two cables in place.
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| iPod cable installed |
Next was the GPS antenna. You might not need to do this, but the W505 supports the docking of a Blackbird II Nav unit, which we intend to add soon, so I wanted to get an antenna in place. After some experimenting with a portable GPS (Garmin 176C) and the external antenna, I determined that the antenna works best when sitting horizontally and that somewhere near the front of the dash would be a good location.
I decided to remove the upper vent panel. It’s not too easy to figure out, but once I understood how it was put together, it was pretty straightforward.
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| upper vent panel removed |
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| Placing the GPS antenna |
Here is the antenna in its final resting place.
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| GPS antenna installed |
Next finalize the actual mounting of the head unit. The original Scosche face plate I had was really robust, and before I started this work, I was thinking that it might work as the only support point for the head unit. The Metra unit is much less robust, so I decided I needed to support the unit in some way. To my way of thinking, after looking over the center dash for a while, there are two ways of doing this; one would be to build a bracket out of some kind of metal strap, attaching it to the back of the unit, and attaching it to some part of the dash; the other way is to support the unit on the rigid plastic shelf just below the head unit. The shelf is triangulated plastic and is very solid.
I decided to simply make some closed-cell foam wedges to attach to the bottom on the head unit. The wedges would rest on the shelf when everything is installed. This photo shows the fine, precision engineering required to fabricate such mounts.
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| Foam marked for cutting |
By playing around with various pieces of foam (left over from unpacking from some piece of computer equipment) I was able to determine that I needed 3 wedges of this shape. I cut them using a bread knife, and then fastened them to the bottom of the head unit with ‘Dual-Lock’™. The next photo shows the foam in place, notice that the center block has a cut out to avoid blocking the vent holes on the bottom of the unit.
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| Foam wedges on underside of Alpine unit |
Tidy up the wiring and cables, bundling them and using cable ties to make everything neat, hook it all up, and slide the head unit into place. Before you screw everything down, run a smoke test to make sure you haven’t pinched anything, or yanked something loose. Screw the head unit down (4 torx screws, two top and two bottom)
You should have something that looks like this.
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| Unit in place |
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| Finished installation |
Turn the unit on and...
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| Victory! |
Since the installation we have discovered that the Blackbird unit supports Bluetooth cell phone integration. Important here in Washington state as a hands-free law has just gone into effect. The bad news is that the integration requires installing a microphone. We're working on it.
Also a clarification. If you want to use the steering wheel buttons to control the stereo you will have to install a CAN-BUS adapter. You will still have to add something like the TR-7 to get in-flight video. Me, I use the steering wheel to steer and prefer that it not be all junked up with accessory controls; so no need for CAN-BUS. I'm odd that way.