Hall Sensor Testing

I have been testing the 3 hall sensors on my ebike, as the controller is reporting an '03' error.
I have applied+5v /dC to each of the sensors ,and then watched on my analogue voltmeter as I slowly rotate the wheel containing the sensors backwards.
I believe what I should see is the voltage switching from +5v to zero as the wheel rotates. I initially thought they were behaving as they should, but when I slowed the rotation right down I could see that one of the sensors was failing to drop to zero volts. I presume that's why the controller is reporting an error and why the motor fails to start when the throttle is actuated?
Anyone know anything about testing Hall sensors? Any advice appreciated.

 

Yep, understand the basics of the 5 v should be heading up the signal wire when the magnets activate it. My issue I think is, that the switch off isn't complete-the voltage is not dropping to zero. I first thought everything was o.k when I tested it with a digital meter, intuition made me swap to an analogue meter, and that's when I noticed the voltage not dropping totally to zero. I suspect the hall sensor has seen better days!

 

That's as maybe Derrick, but it's an ebike I'm talking about!

 

Thanks for the link Finm. Interesting, I suspect if I was to look at the signal output using an oscilloscope I would see that it isn't performing as it's designed to. It's a solid state device, and it's been working in a hot environment for many years, sometime they fail i guess.

 

I have tried both methods.
First I isolated the electric motor from the controller, then using an external power supply I connected 5 volts to the positive/ negative of each of the 3 phases of the hall sensors and observed what I reported previously.
I then did the same test with everything connected up- controller, and LCD screen, using my probes to test the voltage output from each of the signal wires. Same result, it appears that one of the Hall sensors isn't dropping the output to zero.
That's why I presume the controller is reporting an error?