{
  "node": {
    "id": "term:limp-home-mode",
    "type": "Term",
    "label": "Limp-home mode",
    "properties": {
      "id": "limp-home-mode",
      "name": "Limp-home mode",
      "aka": [
        "limp mode",
        "fallback mode",
        "degraded mode"
      ],
      "section": "topic-data",
      "definition": "A reduced-performance state the vehicle or BMS enters after a fault that is not severe enough to shut down, such as a lost temperature sensor or a failed balancing channel. Power and charging are derated so the driver can reach safety or a workshop, and a fault code records why.",
      "related": [
        "derating",
        "dtc",
        "state-of-power",
        "bms",
        "functional-safety"
      ],
      "url": "https://lemonergy.com/learn/glossary/limp-home-mode/",
      "mentions": [
        "temperature-sensor"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:5187",
      "source": "term:limp-home-mode",
      "target": "topic:topic-data",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5188",
      "source": "term:limp-home-mode",
      "target": "term:derating",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5189",
      "source": "term:limp-home-mode",
      "target": "term:dtc",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5190",
      "source": "term:limp-home-mode",
      "target": "term:state-of-power",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5191",
      "source": "term:limp-home-mode",
      "target": "term:bms",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5192",
      "source": "term:limp-home-mode",
      "target": "term:functional-safety",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/limp-home-mode/temperature-sensor",
      "source": "term:limp-home-mode",
      "target": "term:temperature-sensor",
      "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:derating",
      "type": "Term",
      "label": "Derating",
      "properties": {
        "id": "derating",
        "name": "Derating",
        "section": "topic-pack",
        "definition": "Reducing the allowed charge or discharge power as the battery approaches a limit — low temperature, high temperature, high or low SOC, or age. It is how a BMS keeps the cells safe while letting the vehicle do as much as it can.",
        "related": [
          "state-of-power",
          "bms",
          "operating-temperature",
          "fast-charging",
          "limp-home-mode"
        ],
        "url": "https://lemonergy.com/learn/glossary/derating/",
        "mentions": [
          "state-of-charge"
        ]
      }
    },
    {
      "id": "term:dtc",
      "type": "Term",
      "label": "Diagnostic trouble code",
      "properties": {
        "id": "dtc",
        "name": "Diagnostic trouble code",
        "abbr": "DTC",
        "aka": [
          "fault code"
        ],
        "section": "topic-data",
        "definition": "A coded fault a controller stores when a check fails — a cell overvoltage, a sensor out of range, an isolation fault — with a status and often a snapshot of conditions when it occurred. Reading and interpreting DTCs is the first step of any battery root-cause analysis.",
        "related": [
          "uds",
          "bmu",
          "insulation-resistance",
          "freeze-frame"
        ],
        "url": "https://lemonergy.com/learn/glossary/dtc/",
        "mentions": [
          "insulation-fault"
        ]
      }
    },
    {
      "id": "term:state-of-power",
      "type": "Term",
      "label": "State of power",
      "properties": {
        "id": "state-of-power",
        "name": "State of power",
        "abbr": "SOP",
        "section": "topic-state",
        "definition": "The maximum charge or discharge power a battery can deliver for the next few seconds without breaking a voltage, current or temperature limit. The BMS recomputes it continuously from SOC, temperature and resistance and sends it to the motor controller.",
        "unit": "W",
        "related": [
          "power",
          "state-of-charge",
          "continuous-current",
          "derating",
          "bms",
          "state-of-function"
        ],
        "url": "https://lemonergy.com/learn/glossary/state-of-power/",
        "mentions": []
      }
    },
    {
      "id": "term:bms",
      "type": "Term",
      "label": "Battery management system",
      "properties": {
        "id": "bms",
        "name": "Battery management system",
        "abbr": "BMS",
        "section": "topic-pack",
        "definition": "The electronics and software that keep a battery inside its safe window: measuring every cell voltage and many temperatures, estimating SOC and SOH, balancing cells, computing current limits, controlling the contactors and reporting over the vehicle network.",
        "related": [
          "state-of-charge",
          "cell-balancing",
          "state-of-power",
          "cell-supervision-circuit",
          "contactor",
          "can-bus"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/bms/",
        "mentions": [
          "state-of-health",
          "cell-voltage"
        ]
      }
    },
    {
      "id": "term:functional-safety",
      "type": "Term",
      "label": "Functional safety",
      "properties": {
        "id": "functional-safety",
        "name": "Functional safety",
        "abbr": "ISO 26262",
        "aka": [
          "ASIL"
        ],
        "section": "topic-hvsafety",
        "definition": "The discipline, standardised for vehicles in ISO 26262, of making sure electronic failures do not cause harm. Battery functions such as overvoltage protection are classified by risk into ASIL levels A to D, which set how redundant and verified their hardware and software must be.",
        "related": [
          "bms",
          "high-voltage-interlock",
          "insulation-resistance",
          "fmea",
          "mcu",
          "iso-13849"
        ],
        "url": "https://lemonergy.com/learn/glossary/functional-safety/",
        "mentions": []
      }
    },
    {
      "id": "term:temperature-sensor",
      "type": "Term",
      "label": "Temperature sensor",
      "properties": {
        "id": "temperature-sensor",
        "name": "Temperature sensor",
        "abbr": "NTC",
        "aka": [
          "thermistor"
        ],
        "section": "topic-thermal",
        "definition": "Usually a negative-temperature-coefficient thermistor glued to a busbar or cell surface, with a few per module. Because sensors read the surface, the hottest point inside a cell can run several degrees higher than the BMS sees.",
        "unit": "°C",
        "related": [
          "bms",
          "thermal-management",
          "operating-temperature",
          "derating",
          "thermocouples-rtds",
          "virtual-temperature-sensor"
        ],
        "url": "https://lemonergy.com/learn/glossary/temperature-sensor/",
        "mentions": [
          "busbar"
        ]
      }
    }
  ]
}