Auto Meter sensor setup in AIM RS3

[Spengo]

I recently upgraded my data logging system from an old out of date Race Technologies logger to the MXm and am having some trouble setting up a couple of the sensors. I thought I was very smart finding the specs on the manufacturer's website and plugging them in as custom sensors in RS3 but while they appear to be functioning, the values displayed are nonsensical. Is there something I am missing? Do these sensors require a pull up resistor in the wiring? I don't remember seeing anything in the wiring to the old logger. Maybe I'm wrong about what sensors they are? Based entirely on how they look I am guessing that the water pressure sensor is this one:
https://www.pegasusautoracing.com/pr...asp?RecID=1831
and the oil pressure sensor is this:
https://www.pegasusautoracing.com/pr...asp?RecID=1830
manufacturer data is here:
https://www.autometer.com/sensor_specs

[Teuobk]

Unfortunately, you can't just assume their response curves based on external appearance. Different manufacturers, and even different models from the same manufacturer, can have vastly different responses while looking outwardly identical.

The good news is that it's pretty easy to calibrate thermistors using water that you gradually heat, a multimeter, and a known-accurate thermometer. Put the unknown thermistor in the water (sealed side only!), measure its resistance (from the stud to the threaded case) with the multimeter, and check the actual temperature of the water using the thermometer. If you do that at about 100 F, 150 F, and 200 F, that will be enough to fit a curve, which you can then enter into RS3.

You can do something similar for the pressure sensor.

Jeff

[David Ferguson]

Both of those sensors are resistive type, and they vary their resistance to the chassis ground. You would normally provide a pullup resistor to a reference voltage, which would create a voltage divider. AiM makes a part that does this for the pressure sensor (they use the isolated ground version with two posts), but we no longer carry that as all the pressure sensor are solid state now. Here is the part from Pegasus:

https://www.pegasusautoracing.com/pr...asp?RecID=6158

The AiM fluid temp sensor would be an easy replacement for your water temp (not pressure) sensor and has a calibration in Race Studio. This sensor has the pullup built into it's wiring.

https://www.pegasusautoracing.com/pr...Product=MC-201