Coolant Temperature High

Critical
BYD · Thermal Management

This warning light indicates the electric drive system coolant is overheating (EV models) or the engine coolant is overheating (DM-i hybrid models). In DM-i vehicles, extreme conditions such as hot weather, sustained hill climbs, or high-speed driving may cause the engine to overheat.

Stop driving immediately

Pull over to a safe area immediately and wait for the light to turn off. Do not continue driving while the coolant temperature is high, as this may permanently damage the engine or electric motor. Resume driving only once the temperature has returned to normal. If this warning appears frequently, have the cooling system inspected by a qualified technician.

  • Coolant level low
  • Coolant leak
  • Coolant pump fault
  • Thermostat fault
  • Blocked radiator
FieldValue
CodeBYD_WL_021
SystemThermal Management
SeverityCRITICAL
Can drive?no
Data confidence: Community This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.