could a faulty lambda sensor NOT trigger the engine warning light?

the question is in the title folks. My bike has been diagnosed as having an 'inoperable lambda sensor which is not toggling'. In another thread it has been suggested that the engine warning light would come on - which it hasn't.
Thanks
Mike

I'm unsure what faults automatically trigger the engine warning light. But.. assuming your sensor IS genuinely faulty, & the engine light is OFF...well that kinda answers the question.The dealer will replace the sensor I assume? see how it goes after that.