I am in the middle of replacing the rear turn signals on a '83 Honda XL600. This bike is new to me and came without the signals. When I plug the signal into the appropriate connections under the seat the signals do not work. Here is the current scenerio: When new signals are plugged in the the left front signal works but not the rear. The front is on without flashing. When I use the right signal neither the front or the rear works and I hear a buzzing sound comming from the battery compartment. Any idea's on how to troubleshoot this would be greatly appreciated. Thanks.