Coolant temperature
Coolant temperature |
The coolant temperature gauge gives the driver information on engine coolant temperature.
The main instrument unit receives information from the temperature sensor located in the left-hand end of the cylinder head where it is contact with the coolant. The temperature sensor is of NTC type. The main instrument unit measures the coolant temperature by applying 5 V to the sensor from pin 15 (K22) via an integrated 680 Ohm resistor. The sensor is grounded via main instrument unit pin 7 (K22). The voltage across the resistor in the main instrument unit is proportional to the coolant temperature. Information on the current coolant temperature is sent out on the bus.
The coolant temperature gauge's scale is divided into 5 fixed breakpoints. The main instrument unit is programmed to move the gauge needle to the fixed breakpoints at certain specific temperatures to give a steady reading at normal coolant temperatures.
The following breakpoints are programmed in the main instrument unit (factory setting):
Gauge needle:
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Coolant temperature
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-into "blue" zone
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30°C (fixed value)
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-out of "blue" zone
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50°C
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-into "horizontal" position
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80°C
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-out of "horizontal" position
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115°C
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-into "red" zone
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129°C
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-out of "red" zone
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130°C (fixed value)
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