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I'm looking to install an additional air temp sensor (Honda IAT) in my bay to monitor engine bay temps. Using eCtune, I can just utilize pin D10. Has anyone done this before? Apparently I need to cut resistors R136 and R138 in order to make this work.
There is a scalar table for Volts -> Units. The honda manual only shows Ohms -> F' for the factory temp sensors. Can I just check the box for "Honda Temp sensor" and be on my way?
Unfortunately the ectune forum is now down for good I think so all that archived info is now inaccessible
The ECU has an ADC inside to convert analog to digital values (understandable by the processor). R136 and R138 are part of a resistive divider, you must remove them in order to achieve more accurate readings.
For the calibration, use a thermometer to check your ambient temperature near the secondary IAT sensor, then adjust the table for that voltage value, in other words: for 50F move the voltage scale and match it on eCtune. then repeat it using a hairdryer to warm the air. Do this with two or three values. Interpolation will do the magic then
That was my plan, to just wing it until I got it close. I could also pull the stock temp sensor out and lay them side by side and match the 2 together outside of their final environments because ultimately I want to be able to compare temps before and after turbo to monitor efficiency.
HONDATA recommends/requires a "pull up" resistor to be used. Given, this is on their board, but since temperature sensors aren't linear like they say and it may still be required due to voltage readings. I had to use one on all my sensors that's for sure (bought a 100 pack LOL). Then again, I don't have any experience with eCtune and it's built in scalar.
Utilizing analog inputs: D10 ELD
