|
Yeah, I ran into that when I tried direct-driving an optoisolator with the VSS signal. The VSS really doesn't put out much current, so it's easy to drag down the signal so the ECU, speedo and cruise control can't see it. That shouldn't be a problem with the MPGuino's VSS input circuit... It's pretty low-draw. I've used the same configuration on my own creations.
Re-check your wiring connections... There might be a loose strand of wire shorting the VSS line to ground. Check the car end of the wires too.
|