Issue with Arduino Uno and Turnigy Marine 80A-HV ESC

Yes, it's hooked up correctly (signal and ground connected, no BEC power connection). I've tried pulses ranging between 500 and 2200 with no dice. The RC receiver spits out a PPM pulse ranging between 1125 us and 1875 us. Replicating that pulse with with the Arduino does not solve the problem.