Have you taken them apart and make sure they're clean inside the plunger? 90% of ours here in rice jam up behind the plunger. Take the 2 black chutes and plunger off and look inside and make sure it's clean. Sometimes if that happens it pops a fuse and it's pretty simple to fix as well. Those things are a pain though and are expensive to replace. If you have to go through Mother Deere then get a reman.