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(Post Link) post #17 of Old 27-04-19 Thread Starter
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Originally Posted by Henrik_45 View Post
I have checked the workshop manual and it is not mentioned anywhere at which temperature level the low speed and high speed should kick in.

As the 97C kick in for low speed you mention is reported by the Engine ECU it can't be a temperature sensor problem.
The temperature sender is just a NTC resistor (NTC stands for Negative Temperature Coefficient)
The resistor decreases with higher temperature and the Engine ECU just measure the resistance and use a look-up table to convert the resistance to a temperature.
A certain resistance corresponds to a certain temperature

So it seems the software in your Engine ECU is set to enable the low speed fan when the Engine ECU measure 97C cooling water temperature.

As the temperature sender includes a second NTC resistor for the gauge there can be a mismatch between the temperature reported by the Engine ECU and the temperature shown on the gauge.

I can try on my own 2.5 V6 to see at which temperature level the low speed kicks in.
My Car is a CF3 version, has only 1 temp sensors that is sending to the ECU and the Gauge,also i changed it 3 times and same issue even the gauge i just changed it, the previous owner sold it for this issue, and i thought its something i can fix but i think this will kill me before i fix it
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