Battery Energy Control Module

Manages the high-voltage battery — monitoring cell voltages and temperatures, balancing the pack, controlling its cooling and deciding when the contactors may close. Like the transmission module before it, it has no direct control of the dashboard warning lamp and must ask the engine module to illuminate it, which produces a request code that names no fault. That matters more here than anywhere else in the corpus, because the part people assume is at fault is the most expensive one on the vehicle: "the battery module asked for a warning light" is not evidence that a pack needs replacing.

Also known as: becm, battery management system, bms, hybrid battery ecu, battery control module, battery ecu

Referenced by 228 codes

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Codes involving this component (228)

Other components in Hybrid Propulsion

Information, not instruction

CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.

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