Unless you connected it incorrectly the difference between the two wouldn't of been a problem.
If, as I suspect, you connected with reversed polarity then its most likely you've just blown a fuse.
Getting to the fuses is tricky and you need surface mount soldering ability to fix, so the fact you need to even ask what could be wrong means its likely to be beyond your ability to repair. Take it to your local repairer.
Hw
July 2008