Modern Vespa

Can anyone please tell me what the resistance reading for a 2015 GTS 300 Super Sport speed sensor should be please.
I have ABS light showing continuously & speedo not working - from previous posts thought this could be the rear speed sensor.
The workshop manual says speed/phase sensor value should be 100 to 150 Ohm but the photo does not look same as my fitted sensor which measures 100 MegOhms.
Any advice appreciated, thanks.

100 megohms points to an open circuit. Are you reading directly at the sensor?

Thanks for your response.
Yes, unplugged sensor from the wiring harness so it was isolated & then measured directly between the 2 pins.
I suspect it may be the sensor but when unplugged & ignition switched on I get the ASR as well as the ABS light lit which I wouldnt expect if the sensor had failed.
I was planning to compare measurements between front & sensors but the front sensor plug looks to be difficult to get to without dismantling the bodywork.

why wouldn't you expect an ASR light if you unplug the sensor?

If the sensor is truly open circuit, it'd not make a jot of difference whether the sensor was connected or not.

yeah, but not really my point. unplugged sensor would mean no signal. no signal would mean error light (both). this is not a comment on condition of sensor when plugged in

Thanks for your responses.
Does anyone have any experience of measuring the sensor so that I can use that value for reference?

The sensors are just coils - so a resistance of 100 to 150 ohms sounds just right.

Using pins to pierce the wiring very close to the sensor, measure there. You may just have a break in the wires or more likely where the wires join the connector.

Thanks jimc.
It looks as though my sensor has too high resistance so I will try to source a replacement & update.