Thanks johu

I am using an off the shelf controller which has 0 to 5V analogue inputs, so cannot change the interface without designing and building additional hardware that sits outside the controller which I would like to avoid.

I am curious how these sensors are interfaced in automotive ...

I am using a CCS Type 2 connector which has PT1000 RTD temperature sensors on the DC and AC power pins.

What method do control units typically use to measure RTD sensors ?

I have used NTC thermistors before, consisting of a pull up resistor on an analogue input, but I have never used RTDs before ...