Thursday, October 6, 2011

The Final Product

Unfortunately for this project all I've got is photos of the final product, and none of what's going on under the dash. I have since sold my GEM Car as I've moved to a neighborhood with no immediate access to the slower streets needed to really enjoy one of these cars. Ah beach life... I miss Ocean Beach and my GEM, but am glad to have a little more room, even if the road to the beach is longer, and FASTER. No worries though, I explain in the text below how everything was done.

If you want a stereo for your GEM Car that costs over $1000, and is installed by the dealer, this site is NOT for you. Just go to the dealer and pull out your credit card. The stereo install described here costs less, and sounds better, but does require some careful work on your part. Both the dealer stereo install and this install requires drilling into some parts of the GEM. Admittedly this install includes some more drilling and cutting than the dealer install, but I think you get better placement of the stereo and speakers.

IMPORTANT: Always turn OFF the master disconnect switch found under the GEM car front seat before working with any wiring even if it's just the low voltage wiring for the stereo you'll be handling. Better safe than sorry. And on that note, use this guide at your own risk.

Flip Face Stereo

The stereo I installed has a flip face that automatically opens when the "ignition" is turned on (shown in photo). It also automatically hides when the car is turned off. I originally had a Kenwood detachable face stereo in the car, which worked for awhile until the vibrations of the car proved too much for the face connection. Eventually the connection started to short out when driving.

I recommend using a stereo with a non-detachable face, if you can find one, or the JENSEN flip face like I used. I know.. JENSEN is not the hippest brand out there, but try to find another one with an automatic flip face! If the Batmobile has a stereo, it probably works like this one!

In order to get started on this job you'll need to remove the dash. This is easily done by following these steps:

Open hood.

Unscrew two bolts going into the dash cover from the front of the car located just under the windshield. I believe these were torx bolts, though may be different depending on your GEM model.

Return to the seated area of the car and pull the dash cover up and toward the rear of the vehicle. It should pop loose. If not you may have more screws to remove for you GEM model.

Once the dash is removed mark the location and profile for your stereo on the dash cover and VERY carefully cut out the profile from the front of the cover. I believe I used a dremel, but a jigsaw may also work, or handsaw for more control. It might be a good idea to put tape where you won't be cutting in case something slips. You wouldn't want to scrape up the dash.

I held the stereo in place in the car by simply drilling holes for two bolts on the frame under the dash on either side of the stereo, and running a piece of galvanized metal strap over the stereo to the bolts. I also placed a piece of rubber under the stereo to reduce vibration and rubbing of metal-on-metal. A cheap rubber door mat cut up to match the stereo footprint works well for this, but you could probably use a mouse pad or something similar. This method of using a strap works well because you can position the stereo where you like front to back, so the stereo sticks out just a bit from the hole in the dash, and then tighten down when you've found the right position.

Crossover Speaker Kit

I used a Kenwood speaker kit that came with two woofers, two tweeters, and two crossovers. The kit is simple to wire together. Essentially one woofer and one tweeter go with one crossover. Then the channel output from the stereo goes to the crossover. One set for the right channel, and one for the left. This is all covered in the manual that comes with the speaker kit. And also shown in the diagram below.

Enlarge the photo to see the small round tweeters mounted in the left (and right, not visible) corners. The tweeters were installed by drilling a hole in each corner of the dash. The tweeters are small enough that a circular drill bit can be used to make the holes. I believe these tweeters need a 1 1/2" hole, but check the speaker kit manual.

What's THAT on the back of your GEM??? That's for another posting, but it's a dog carrier.  Note the two woofers mounted below the seats. Again, each woofer goes to its own crossover shared with a tweeter. The holes that need to be cut for the woofers are obviously larger than those required for the tweeters, and need to be made with a jigsaw instead of a drill. I believe the size of these holes are 4 15/16", but again check the speaker kit manual.

The crossovers, which are essentially small plastic boxes with some circuitry, are mounted on the same frame found under the dash to which the stereo is strapped down. Simply drill two holes matching up with the mounting holes of the crossover and secure to the frame with bolts.

Wiring Everything Together

Take a look at the wiring diagram. First you'll notice a few things not mentioned above, including a stereo battery, diode, and antenna. The stereo battery provides power to the stereo when the GEM Car is off. Unfortunately, unlike a regular car, the GEM Car does not provide 12 volts when turned off. This battery is used to provide the small amount of power the stereo needs to maintain it's memory to keep time set, presets, CD play location, etc. Without this battery your stereo will start up each time completely reset, which can be annoying. The battery is mounted under the dash in the front left corner. There is a small compartment that the battery will fit in, and again this is strapped down like the stereo with the galvanized metal strap and rubber wrapped around the battery.

The diode in the wiring diagram is to prevent back current to the GEM Car Circuit board from the stereo wiring. Do NOT skip adding the diode! This is some good insurance for protecting your circuit board.

I chose a simple marine antenna for my car. I thought it fit with the car's aesthetics, plus it's flexible and not easily damaged. I drilled a small hole in the hood, and ran the wire to the compartment under the dash to the stereo.

Adding a Solar Panel

I added a solar panel to charge the stereo battery when the GEM Car wasn't being used, and of course parked in the sun. No point to this if you're parking in the garage 90% of the time! The charger I selected is a basic trickle charger commonly used for campers and other vehicles that stay parked for a long time with power being used when the engine is not running . This is not needed for the GEM Car stereo install, but I did find without it the stereo battery would run out of power in a few months. For the rare occasion of a dead battery I ran a small battery connection out from under the dash so I could hook up a 12 volt battery charger without removing the dash.

Click here to view Amazon Store for all parts listed above.

Good luck on your stereo install!

Other Rojects

Roger + Project = Roject (my wife's equation)