2009 Toyota Camry Hybrid OBD2 Code P2103

My Camry has been running great and problem free. I got ~32mpg of this hybrid. It in OK but not as high as I would like it to be. Last week, the "check engine" and the "check hybrid system" lights came on. Since the light came on, the Camry became very sluggish (slow) even I pressed on the gas pedal. 2 days later (Dec 12, 2015), I took it to a local Autozone to pull the code.

I pulled the OBD2 code is P2103 - Throttle Actuator Control Motor Circuit High Input.

I suppose the step of pulling the code has reset the code. The "check engine light" went off and the Camry went normal for the last 15 miles. I googled the internet and they are not much information to talk about P2103. Could you provide some guidance when was the possible causes of P2103 and your recommendations to trouble shot / fix the problem please? Many thanks.