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SDS RPM Pulses per Revolution?

majuro15

Well Known Member
I'm getting inaccurate RPM numbers on my AFS5XXX screens. I know I can adjust the settings but don't know how many pulses per revolution the SDS ECUs give off? Anyone know? I have the EM-5, full SDS setup.
 
3 pulses per crank rev. You can have a 5V signal from pin 12 (green wire) or 12V signal from pin 22 (yellow wire).
 
Thanks Ross! So I am 90% I need the 12V so I have the yellow wires hooked to the EFIS. If I actually need the 5V, would that affect the value the EFIS is reading?

I'll try the 3 setting tomorrow. I did play with that a second today but feel like the EFIS was still reading high.
 
Thanks Ross! So I am 90% I need the 12V so I have the yellow wires hooked to the EFIS. If I actually need the 5V, would that affect the value the EFIS is reading?

I'll try the 3 setting tomorrow. I did play with that a second today but feel like the EFIS was still reading high.

Check the minimum trigger voltage on the EFIS for the tach pin you're using. The 5V could be too low to give an accurate reading.
 
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