# P1B77 on the 2018 Kia Optima

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

This code is specific to a manufacturer and is not described here.

## Bulletins for this model year that name P1B77

- [10230492](https://open.wenmarpro.com/bulletins/10230492), 2023-02-02: TECHNICAL SERVICE BULLETIN: SERVICE ACTION: BMS/OPU/MCU LOGIC IMPROVEMENT \(SA411\) \- This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This bulletin provides the procedure to improve the logic of the Battery Management System \(BMS\), Oil Pump Control Unit \(OPU\) and Motor Control Unit \(MCU\) on some 2017\-2019MY Optima \(JF P/HEV\) vehicles, produced from August 25, 2016 through September 13, 2018 \(refer to page 8\) in order to improve the BMS diagnosis logic, OPU judgment logic for DTC P1B77 \(High Voltage Battery Pre\-Charging fault\) and MCU communication logic.
- [10174515](https://open.wenmarpro.com/bulletins/10174515), 2020-05-05: TECHNICAL SERVICE BULLETIN: SERVICE ACTION: BMS/OPU/MCU LOGIC IMPROVEMENT \(SA411\) \- This bulletin provides the procedure to improve the logic of the Battery Management System \(BMS\), Oil Pump Control Unit \(OPU\) and Motor Control Unit \(MCU\) on some 2017\-2019MY Optima \(JF P/HEV\) vehicles, produced from August 25, 2016 through September 13, 2018 \(refer to page 8\) in order to improve the BMS diagnosis logic, OPU judgment logic for DTC P1B77 \(High Voltage Battery Pre\-Charging fault\) and MCU communication logic.