Vehicle speed sensors?

[DatNissan]

I have a 97 Maxima GLE auto, and have about 103k on it and I've recently got a check engine light on with a vehicle speed sensor malfunction code. I replaced the sensor and harness it comes with, with batt disconnected and then cleared the light. The light reappeared 2days later, looking at a manual I noticed this vehicle ccarries 2 sensors on the trans a vehicle speed and a revolution sensor. I replaced that batt disconnected replaced sensor and the same thing 2days light comes on. Is there anything else I am missing? I am thinking wheel sensors at this point but the scan tool clearly says vehicle speed malfunction. Any one ?