Chevrolet Preliminary Evaluation PE23022: Loss of Motive Power due to the Battery
2019 Chevrolet Volt
Electrical System Electrical System:Propulsion System Electrical System:Propulsion System:Traction Battery:Management System/Energy Control Module (Bms/Becm)
On November 29, 2023, the Office of Defects Investigations (ODI) opened PE23022 to investigate allegations of a loss of motive power, including a stall, reduced power state, and/or a no start condition due to the Battery Energy Control Module (BECM) in model year (MY) 2016-2019 Chevrolet Volt passenger car vehicles manufactured by General Motors (GM). The BECM is located within the high voltage electric vehicle (EV) battery pack and monitors the temperature, current, and voltage of the high voltage battery cell groups. GM stated that the root cause was identified as an internal failure leading to a loss of communication within the BECM and does not pose a risk to motor vehicle safety. GM further stated that the failure cannot result in a complete stall, only a reduced power mode, no start condition, or a no charge condition. GM additionally stated that if these conditions occur, the driver will be warned via a Malfunction Indicator Lamp (MIL) and/or a reduced-propulsion message in the Driver Information Center (DIC). Data received and analyzed by ODI from all sources indicates that nearly all related BECM failures caused conditions aligning with GM-??s predicted outcomes. Despite the large number of warranty claims, nearly all failures were not safety-related, i.e., not a stall or reduced power mode. ODI isaware of a single minor crash and no injuries or deaths. In March 2024, GM issued Special Coverage N232432680, which was mailed to consumers, addressing BECM failures in certain MY 2016-2018 Chevrolet Volt vehicles. This special coverage provides an extension of the warranty coverage for the BECM from 8 years / 100,000 miles to 15 years / 150,000 miles for all 2016-2018 Chevrolet Volts. Additionally, GM stated that replacement components are sourced from a different supplier and not susceptible to the failure. In view of the Special Coverage issued by GM, the existing warranty coverage already in place, and the low number of safety-related occurrences, ODI is closing this Preliminary Evaluation (PE). The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The Agency reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.
