Testing Procedures
WARNING: This page is about a different car, the 2003 Toyota Prius, 2002 Toyota Prius, and 2001 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
To start testing, check what DTC is set for the HV control system. If an output HG code is recorder, repair HV control system according to the output code. If malfunction indicator light remains ON, check that HV ECU is connected to malfunction indicator light.