Hey guys, first post. Bummer it has to be under these circumstances!
I created a battery charger in which the Arduino would use a voltage divider to read the voltage of the 9V connected to the vin pin. Everything was working perfectly, until it wasn't. Suddenly the vin pin no longer works, but the circuit still works when plugged into USB power. Vin won't power the arduino even when it's just straight into the battery with nothing else plugged in.
I'm not sure what happened, the only possibility I can think of is that I may have inadvertently switched polarity on the vin pin
Is there any way I can diagnose/repair or work around this?