Make your own eTrex data cable

I paid AUS$270 for my eTrex (At Globe Trekker in Brisbane) and the genuine Garmin data cable is AUS$80. At 1/3 of the price of a new receiver there are better ways of making this 3 wire lead.

Caution: If you damage your GPS using a non-genuine connector you will void your warranty.

Making your own eTrex data cable is easy enough. Making the plug suitable to fit into the awkward new Garmin connector is the difficult part.

My first attempt at a data cable

I was lucky enough to find an old mobile phone battery charger which had three pins already mounted in the correct spacing. I shaped the contactor part of this old mobile phone battery charger so it would slide nicely into the slots on each end of the eTrex data connector. This took a while to get it to fit accurately.

Another option

I stumbled across this great idea. It is a very simple way of making an eTrex/eMap connector out of a cut up credit card. I think this is probably the easiest and quickest method of making your own.

You will need an old credit card, a small drill or hot needle, and some pins like these:

You will find theses pins
at most electronic stores

1. Take the credit card and carefully cut it to size. Use sandpaper to shape it.
2. Three holes (or 4 if you want to experiment with external power) should be made with either a hot needle or small drill. You will need to position these holes so the pins will mate with the eTrex correctly.
   If you use a hot needle, do it from the bottom side so that any excess melted plastic doesn't interfere with the mating surfaces.
   
3. Add some epoxy to provide strength and insulation
4. Wiring instructions

The easy option

You can also purchase a connector called an Eplug which is an aftermarket injection molded connector. Click here for details on the Eplug. The plugs are very cheap and I wish I had known about them before I spent an afternoon building my own!

USB Cables

Pfranc now make a USB cable so you can connect your eTrex or eMap to a USB port.
Click here for details

External Power

Apparently the official range for the eTrex is 3VDC +/- 0.15V. I have read that eTrex works from 1.75V to 6V, however may tend to get a little warm at 6V. I wouldn't try more than 3 volts on my own eTrex.

The charger only had three pins so I never got around to making a power lead.

Related Links

Commercially available connectors

Wiring Diagrams

USB Data Cables (Off site link)