First off, if you had them installed less than a year ago, let the dealer deal with them. If not, what you need to do is trace the wire coming down the right handle bar to the bullet connector. Unplug the connector and check for resistance. If either of the plugs show open, then the grip itself is bad. Either grip by itself will take down both grips. Hopefully, you already checked the little fuse in the white plastic housing, usually located somewhere under the right pocket. Most likely, one of the grips died, and hopefully you are still under warranty, cause there are no replacement parts that I am aware of. You will most likely be buying a new kit, and then you will have some spare parts. Good luck!!!