Hi Shaun

This is an AC excited type cam sensor (it is covered in the presets on Picoscope Automotive). If you scope the two outer pins at the sensor, (or better still pins 31 & 32 at the PCM) you should see an AC signal on each. It's quite a rapid signal & if the sensor is functioning correctly, you should see that the alignment of the two signals move (in relation to each other) as a ferrous object is passed close to the tip of the sensor.

A bit like this....




It's a shame you didn't deploy the scope before diving in so deep with ECU testing & the like!

You'll know for next time though hey!

Here is a link to something from the archives.

HTH

Dave