Hi Amanda which model of DR do you have. Also provide the model number of the engine so we can assist with charging problems. So for this test you will need a volt meter(multimeter). With the engine off connect the red lead of the ] meter to the positive terminal and the black lead to the negative terminal of the battery. Check the voltage. Should be around 12-12.5 volts. Now the the engine running recheck the voltage. Should be 13.5-14.5 volts. If you are not getting that voltage with the engine running then the charging system isn't working to recharge the battery. After giving us the model of engine then we can give further assistance for checking the charging system if needed.