Maybe this helps:
I found a similar problem: USB cigarette ligher (an expensive one) charger, and the phone (Nokia C7) won't charge. The solution was somewhat surprising.
Some background info: in the USB plugs, there are 4 wires: +5 V, Ground, +Data, -Data. Only the first two is required for charging, but you have to do something with the rest.
The spec says, they should be connected together either directly or through a maximum of 200 ohm resistor. However, in my charger (optimised for iPhone perhaps?) the +Data was connected to the +5 V through a 24K resistor, and likewise the -Data to the Gnd through a 24K resistor. Removing them and connecting the + and - Data through a 100 ohm resistor, the charger works perfectly. Too bad though, that you need a soldering iron for this...
I found a similar problem: USB cigarette ligher (an expensive one) charger, and the phone (Nokia C7) won't charge. The solution was somewhat surprising.
Some background info: in the USB plugs, there are 4 wires: +5 V, Ground, +Data, -Data. Only the first two is required for charging, but you have to do something with the rest.
The spec says, they should be connected together either directly or through a maximum of 200 ohm resistor. However, in my charger (optimised for iPhone perhaps?) the +Data was connected to the +5 V through a 24K resistor, and likewise the -Data to the Gnd through a 24K resistor. Removing them and connecting the + and - Data through a 100 ohm resistor, the charger works perfectly. Too bad though, that you need a soldering iron for this...