Inspection Procedure
WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
If INFORMATION CODE 212 is output, after confirming the DTC of the ECM, check and repair the applicable DTC. Prior to repairing it, record the DTC of the HV ECU, freeze frame data and history of operation. Then, clear the DTC and check it one more time after starting the system again ("READY" light ON).