The only sensors that I occasionally "bench test" are zirconia oxygen sensors & inductive pick up sensors (ABS, Cam & Crank sensors etc). These sensors generate their own signals & are simple to test.
I have also been known to take a cam sensor out (hall sensor type) & scope it (still connected to the vehicle harness) whilst I wave a steel washer close to the tip. Dont forget that no signal from a cam sensor, doesn't mean that the sensor is faulty. It could mean that the cam shaft is not turning
Cheers for now
Dave