Etrex will not accept external power

[+Cleenjeep & Danger Girl]

I assembled a car/PC cable using an E2plug and a cell phone charger. I ensured the voltage is correct, at about 4.3Vdc, and the polarity. I have triple checked it. However, when plugged into the etrex, it will not turn on. First time it happened I thought I must have done something very wrong, but then I popped batteries into it, and it works fine.

I made sure the pins are projecting far enough out of the e2plug, and checked voltage/polarity again. Seems A-ok.

I used this previously, but with a different power source, another adapter for another cell phone. But, the adapter was shut in a door, and the housing fell apart, so I had to get another. This one is a bit different, but voltage is still within the etrex's range of 3 to 6 volts, if I remember that part right.

I have heard of the screen going quite dark if the voltage is too high, but that doesn't appear to be the trouble. The screen is not dark, it is not on at all.

 

Any ideas?

[+Cleenjeep & Danger Girl]

I found out what it was. I had been using the wires from the phone charger without opening up the case of it. There was three, a red, a yellow, and an orange. I measured the 4.3V across red and either of the others. So, I chose red and yellow.

When I opened the case of the charger, they were labelled on the board. One was v+, one v-, and one was vs. Yup, the yellow. So, I switched it around, and viola. Works like a charm.

[+Prime Suspect]

So, I switched it around, and viola. Works like a charm.

 

You connected it to a viola? How did that work?

 

[+NightPilot]

You didn't know there was an eTrex connector on the edge, along with a mini-USB connector? Very convenient.