{
  "node": {
    "id": "term:ecu",
    "type": "Term",
    "label": "Electronic control unit",
    "properties": {
      "id": "ecu",
      "name": "Electronic control unit",
      "abbr": "ECU",
      "section": "topic-data",
      "definition": "The general name for any controller on a vehicle network — BMU, VCU, CCU and motor controller are all ECUs. Each has its own address, firmware, diagnostic services and calibration data.",
      "related": [
        "bmu",
        "vcu",
        "ccu",
        "uds",
        "can-bus"
      ],
      "url": "https://lemonergy.com/learn/glossary/ecu/",
      "mentions": [
        "firmware"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:4114",
      "source": "term:ecu",
      "target": "topic:topic-data",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:4115",
      "source": "term:ecu",
      "target": "term:bmu",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4116",
      "source": "term:ecu",
      "target": "term:vcu",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4117",
      "source": "term:ecu",
      "target": "term:ccu",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4118",
      "source": "term:ecu",
      "target": "term:uds",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4119",
      "source": "term:ecu",
      "target": "term:can-bus",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/ecu/firmware",
      "source": "term:ecu",
      "target": "term:firmware",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-data",
      "type": "Topic",
      "label": "Data, communication and electronics",
      "properties": {
        "id": "topic-data",
        "name": "Data, communication and electronics",
        "lede": "The control units, chips, protocols and file formats through which a battery is measured, controlled and logged.",
        "context": "Separate quantities from encoding and transport.",
        "example": "2500 in a log might mean 25.00 °C, 2.5 V or raw counts. Units and scale must accompany the value.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "id": "term:bmu",
      "type": "Term",
      "label": "Battery management unit",
      "properties": {
        "id": "bmu",
        "name": "Battery management unit",
        "abbr": "BMU",
        "aka": [
          "BMS master",
          "master BMS"
        ],
        "section": "topic-data",
        "definition": "The master controller of a battery management system: it collects cell voltages and temperatures from the monitoring boards, runs the state estimation and protection logic, drives the contactors and talks to the vehicle. In some architectures the same name is used for a per-module slave, so a datasheet’s block diagram is the safe reference.",
        "related": [
          "bms",
          "cell-supervision-circuit",
          "bcu",
          "contactor",
          "can-bus",
          "bms-power-modes"
        ],
        "url": "https://lemonergy.com/learn/glossary/bmu/",
        "mentions": [
          "datasheet"
        ]
      }
    },
    {
      "id": "term:vcu",
      "type": "Term",
      "label": "Vehicle control unit",
      "properties": {
        "id": "vcu",
        "name": "Vehicle control unit",
        "abbr": "VCU",
        "section": "topic-data",
        "definition": "The supervisory controller of an electric vehicle: it interprets the driver’s demand, asks the motor controller for torque and the BMS for the power it may give, and decides when the high-voltage system may switch on. The BMS reports to it, usually over CAN.",
        "related": [
          "bmu",
          "can-bus",
          "state-of-power",
          "inverter",
          "ccu"
        ],
        "url": "https://lemonergy.com/learn/glossary/vcu/",
        "mentions": [
          "bms",
          "electric-vehicle"
        ]
      }
    },
    {
      "id": "term:ccu",
      "type": "Term",
      "label": "Charging control unit",
      "properties": {
        "id": "ccu",
        "name": "Charging control unit",
        "abbr": "CCU",
        "aka": [
          "charge control unit"
        ],
        "section": "topic-data",
        "definition": "The vehicle-side controller that manages charging: it detects the plug, talks to the charging station over the control pilot or ISO 15118 and DIN 70121, and passes the current and voltage limits the BMS allows. In some bus and truck architectures CCU also names a central or cluster control unit, so the system diagram decides.",
        "related": [
          "evcc",
          "iso-15118",
          "din-70121",
          "bms",
          "onboard-charger",
          "pantograph-charging"
        ],
        "url": "https://lemonergy.com/learn/glossary/ccu/",
        "mentions": [
          "control-pilot",
          "evse"
        ]
      }
    },
    {
      "id": "term:uds",
      "type": "Term",
      "label": "Unified diagnostic services",
      "properties": {
        "id": "uds",
        "name": "Unified diagnostic services",
        "abbr": "UDS",
        "aka": [
          "ISO 14229"
        ],
        "section": "topic-data",
        "definition": "The standard diagnostic protocol of vehicle controllers, ISO 14229: services to read data and fault codes, run routines, change sessions and flash firmware. A service tool talks UDS to the BMU over CAN to read cell data, clear faults or update software.",
        "related": [
          "dtc",
          "flashing",
          "can-bus",
          "odx",
          "ecu"
        ],
        "url": "https://lemonergy.com/learn/glossary/uds/",
        "mentions": [
          "bmu",
          "firmware"
        ]
      }
    },
    {
      "id": "term:can-bus",
      "type": "Term",
      "label": "CAN bus",
      "properties": {
        "id": "can-bus",
        "name": "CAN bus",
        "aka": [
          "Controller Area Network",
          "ISO 11898"
        ],
        "section": "topic-pack",
        "definition": "The serial network over which a BMS talks to the vehicle or inverter: a two-wire differential bus, defined in ISO 11898, carrying short prioritised messages at up to 1 Mbit/s, or faster with CAN FD. Every node hears every message, and a dominant bit wins arbitration without any collision.",
        "related": [
          "can-high-low",
          "can-fd",
          "termination-resistor",
          "bms",
          "lin-bus",
          "fms-interface"
        ],
        "url": "https://lemonergy.com/learn/glossary/can-bus/",
        "mentions": [
          "inverter"
        ]
      }
    },
    {
      "id": "term:firmware",
      "type": "Term",
      "label": "Firmware",
      "properties": {
        "id": "firmware",
        "name": "Firmware",
        "aka": [
          "embedded software",
          "BMS software"
        ],
        "section": "topic-data",
        "definition": "The software that runs on a BMS or charger controller. Its version decides how SOC, limits and faults behave, so it is tracked like a part number, updated by flashing over CAN or over the air, and recorded in the battery passport.",
        "related": [
          "mcu",
          "flashing",
          "bmu",
          "battery-passport",
          "functional-safety"
        ],
        "url": "https://lemonergy.com/learn/glossary/firmware/",
        "mentions": [
          "charger",
          "state-of-charge",
          "bms",
          "over-the-air-update"
        ]
      }
    }
  ]
}