This code is thrown when the ECM sees low voltage on the TPS signal wire. It is usually caused by the blue wire grounding out (frayed wires by the sensor connector) or by the TPS itself being bad.
You can put a voltmeter on the blue wire on the TPS connector (connected to the TPS) with the key on and you should see cca 0.4V. You can then wiggle the wires or connector and see if the voltage drops lower (well, to 0V). You can also try to exercise the throttle blades several times, watching the voltage again. The voltage should never drop below 0.4V, that would point to a bad TPS.
You can google how to check the TPS, I'm sure you'll find a lot more detailed information than what I'm typing here in short.
Hope this helps.