Hello, and thank you for letting us help you with your automotive question. If both of them stopped working at the same time then it is not the batteries. Either the module that receives the signal has failed or the programming between the FOB's and the receivers is corrupted. Most of the time to fix this you would need to get the system reprogrammed. Try holding the transmitters close the the vehicle and holding down both lock buttons. If the vehicle does not respond then you are looking at going to the dealer and having the module reprogrammed or possibly replaced. Unfortunately due to the programming they do not make this to where you can easily do this yourself.