You can trace the wires and make sure that there is not a bare spot in them or that one of the connections are not exposed. If you are still under warranty then take it back to the dealer and demand new grips. If you are out of warranty then I would strongly suggest getting away from the OEM grips and getting aftermarket heated ones. I put the OEM grips on my XR and after 9k miles the left one is wore down pretty bad, going to have to either replace them or put some grip covers over them.
2011 Cross Roads Sunset Red
OEM short windshield, passenger backrest, crash bars, saddle bag bars, heated grips, vinyl closeouts, tachometer, ambient temp, LED headlight, luggage rack. WD lay down licence plate.