I am trying to use my PICO scope and the PICO Diagnostics NVH feature to measure the wave form and frequency of some ABS sensors fitted to a 2011 Mercedes E Class. The sensors are two pin hall effect type items, however when using the how-to guide https://www.picoauto.com/library/automo ... r-digital/ I fail to get a plausible signal displayed. My question is what do I need to do differently and how is the test setup affected with a two pin sensor? Two pin sensors have a combined signal and earth reference circuit, where the earth reference for the sensor floats at the voltage level of the signal, is this why I cant see a clear square waveform?
Any help is gratefully appreciated, perhaps im missing something simple here or need to make some hardware changes to my probe setup to provide what I need.