Reading RPM and VSS of a car

Using Arduino Project Guidance
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Hi, I’m currently working on a project that requires the input of the RPM and VSS off of the car. I found the ecu pin that gives off the rpm and vss signal (both pulsed), and coded it to display the rpm and vss on the Serial monitor.

I tested it with my function generator, and it prints out the frequency of both just fine when I generated a clean square wave.

However, when I tried to hook it up to my car’s RPM signal, it is stuch reading 38 and doesn’t seem to move. My best guess would be that the low voltage of the car’s ECU is slightly higher than the low threshold of the arduino so it does not register it as 1 cycle.
I’m using FreqCount to get the VSS and PulseIn for the RPM.

I’m also reading an analog signal and it displays just fine with the accurate data

Anyone ever run into this issue or did something similar to this application?

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Is there a reason you don’t just analog pins to capture the data?

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Slumpert:
Is there a reason you don’t just analog pins to capture the data?

Analog pins? The ECU pins give out a pulsed signal, I’m trying to read the frequency using the pulsein and freqcount methods.

Would analog be better at determining a RPM signal? If so, how would I do it?

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Bump