Amazon Fire Smart Phone- Charging Problems

[tali1]

i have a amazon fire smart phone and over the last few months it has stopped charging when using a in car usb 12v and power bars.I have checked the two and other phones charge perfectly.I have changed leads but to no avail.
The amazon fire smart phone will charge on plug in chargers and on laptops/pcs

[Buenchico]

If your reference to 'power bars' means that you're using something like this
http://img.dxcdn.com/productimages/sku_12461_1.jpg
then it's possible that there's insufficient current being directed to the 5V USB socket.

Instead use a 12V converter that shows the power output as at least 2 Amps.

[tali1]

But they worked perfectly before - so surely it can't be the issue with the charging device but perhaps the battery itself ? as i mentioned other phones charge no problems

[Buenchico]

It could even be a problem with the car's alternator. If it's not working as well as it used to it will be delivering a lower voltage, which might mean that the adaptor's output is below that required to charge the phone's battery.

[tali1]

possibly ....but it charges other phones fine..