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Hi im a bit confused with the waveform im seeing...
So upon putting my verus scope on the crank signal wire with the car running im getting a square wave switching on and off at around 2.5v to 0v, the sensor is a 3 wire sensor.
What im confused about is the info on the verus is saying the crank sensor for this car is an inductive type sensor and showing a sample waveform of an AC wave and like i said im getting a square waveform Which would indicate a hall effect sensor right??
The Verus doesn't have the most accurate information. I have also seen inaccurate waveform descriptions.
Usually the square wave is a 0-5v square wave. Not sure if I have ever seen one with 2.5v. It might be out there. What vehicle you working on?
You can rest assured though that if you see a square wave pattern on a 3 wire sensor, there is no way it will ever output a AC Sine wave. 3 wire sensors are always Hall Effect Sensors and 99% of the time 2 wire sensors are Variable Reluctance sensors. There are some wheel speed sensors that are 2 wire sensors but are Hall Effect. The 3rd wire is not there because its grounding through the body of the sensor.
be aware there are quite some 3 wire sensors out there that are NOT digital/hall effect onned but VR sensors. Examples are AudiVW crank and cam sensors. The third wire on these serves shielding. A look at SI and/or a WD will take the guesswork out.
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
Im working on a euro car its a vw fox 1.2 engine code BMD 2006.
Thats what j thought that 99% of 3 wire sensors are hall effect and like i said upon scoping the signal i got a square wave so again i thought theres no way i could get an ac wave
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