2002 Nissan X Trail Fault Code P0120

I have a Nissan X Trail on a 2002 plate, it is a 2.2 Sport, 6 speed manual, LH Drive, 78,000 miles. It is currently off the road with a fault code of P0120 (Throttle Position Sensor) The Maintenance Indicator Light had illuminated twice previously and the car had gone into limp home mode, however on stopping and restating the fault cleared. The fault is now permanent, I have had the potentiometer readings checked and they seem normal , between 0.5v and 5v dependant on throttle position. There are also two connections for a switch, the reading on these in the relaxed position is between 200 & 350 ohms, it goes open circuit as the throttle is depressed. Is this normal and if so what else could be causing this fault code. The throttle sensor has 8 connections on the connector.