change the ploarity of charger 12 v PIN VIN

[zoheir]

hi everyone spv i have a arduino UNO powered by a 12v charger with a pin vine, i change the polarity after larduino does not televerse. please help me

[Railroader]

spv?
Change polarity?

[CrossRoads]

You likely damaged it.
See the diode there, and Vin is after it? The diode protects against reverse polarity.
So the 5V regulator, and the parts after probably saw a high reverse voltage, damaging everything.