This bulletin applies to 2016-2019 Toyota Prius vehicles. Some vehicles equipped with a NiMH HV battery may exhibit one or both of the following conditions after repeated driving on long downhill slopes or while driving in high ambient temperatures, then turned off for approximately one to two hours, then restarted:
- When accelerating from a stop or from extremely low speeds, the vehicle may have a reduction in power.
- The HV battery monitor on the multi-information display continually shows one bar, indicating that the battery state of charge is at it’s lowest level.
The Hybrid Control Computer (HV ECU) logic has been modified to reduce the possibility of these conditions. Reprogram the HV ECU using software version 14.20.019 or later.