Couldnt power up arduino using 12v rechargeable lead acid battery.battery is charged for more than 8 hours and input in given to vin and other is grounded the on and 13 pin LED's are very dim compared to when powered by USB
reading of
vin is 12.05
5v is 2.3v
suggestions required i need to make my projeect wireless and the most crucial part is external power supply
That sounds like a voltage regulator problem. Maybe it is overheating? Have you tried a lower voltage wall wart, like 9vdc? I use a 7.5v wall wart with my Mega/ethernet shield, and the regulator still gets a bit hot.
Which Arduino board are you using? Don you have anything else connected to it?
Arduino uno r3
If nothing is connected to it, then it sounds like you have a bad voltage regulator. Is the voltage regulator getting hot?