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Coolant temperature

Coolant temperature


The temperature sensor informs the ICE about the coolant temperature. This information is then sent to the main instrument in the form of a PWM signal when the ignition is in start or drive position.

Main instrument 1

In main instrument 1, control of temperature indication is in the ICE, i.e. the breaking points in the temperature indication are directly programmed into the ICE, which sends information to the main instrument unit via another PWM output. If the signal from the temperature sensor falls below -60°C (-76°F) or goes above +160°C (+320°F), i.e. outside the temperature range, for more than 0.5 seconds, the ICE will set the pulse ratio at 5%%.

If the temperature signal is above +160C or below -60C, the ICE presumes that there is a short in the temperature sensor or a break in the circuit and a diagnostic trouble code is set.

Main instrument 2

In main instrument 2, control of temperature indication is in the main instrument.

The PWM signal from the ICE has a frequency of 122 Hz and varies linearly between a pulse ratio of 10%% and 90%%, but the main instrument sets breaking points at certain temperatures to keep the temperature gauge needle horizontal within the engine's normal temperature range.