Possible Causes

WARNING: This page is about a different car, the 2003 Toyota Camry. However, it is still accessible from the selected car via links, so may be relevant.

Possible causes are:

If the valve timing does not change from current valve timing or current valve timing is fixed (the problem of the advanced (DTC P0011) or retarded (DTC P0012) OCV) continues after the engine is warmed up and the engine speed at 400-4000 RPM.
Incorrect valve timing.
Defective OCV.
Defective VVT controller assembly.
Defective ECM.