Scoped the AFM and all is as expected....
We scoped the outputs of all four wheel speed sensors and the NSF one does not output a signal (well it does, but its only just above background noise and in the mV range).
We tested the voltage against that of the OSF sensor and the rear sensors and all are the same at around 12.5v and 0.5v on each wire (so wiring and voltage supply from ECU must be OK?)
We swapped the front speed sensors over and the NSF still exhibits no signal.
We 'wafted' a magnet across the tip of the OSF sensor and noted a pulse on the scope - same test on the NSF one results in no pulse.
Whats confusing is that if we have voltage, indicating the wiring must be OK and continuous and that the ECU must be outputing the voltage, why dont we have a signal pulse?
I'm thinking that there may be an internal fault in the DSC ECU that is dragging the signal level down, but thats a pure stab-in-the-dark.
Any more ideas?
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