ECU Coolant Temp Sensor vs Coolant Temp Gauge Sender

[ZeKahr]

Why did BMW use two coolant temp sensors to send the coolant temperature signal? Do these sensors have different resistances calibrated separately for the ECU and temp gauge or something? Wouldn't they be able to send the same signal to the temp gauge and ECU with just one coolant temp sensor?

I looked at my Bentley for information on the temp gauge resistance values but could not find anything. It only has resistance values for the ECU coolant temp sensor. Anyone have the resistance values for the temp gauge sender? Specifically for a 1986 325e.

[tomstin]

The best all in one place document I've found. It has many of the resistance values I think you're looking for http://www.verrill.com/car/e30_idlefaq.shtml

[uturn]

My memory is a little hazy.... I believe the ECU temp sender is two pin type and the temp gauge sender is one pin.