What kind of sensor are you referring to? I mean, is it your colour sensor that's not working?

1. Check to see if everything is wired correctly
2. Is the ambient lighting good
3. Did you program it properly(assuming you need to)
4. Serves connected properly and working?

i have a comprehencive whit ax-s1 head sensor.any distants i choose in task,he does not see, anything.when i check servo manager ,i see the ax-s1 responding well. maybe a video would be good.

So he recognizes what he is supposed to according to your software.... but he doesn't physically move as he is supposed to?... Have you confirmed the servos are connected and in working? Or is there any way to just check the colour sensor by itself to see if it is working?

Power everything down... unplug and check all connections... then plug everything back in again... re-boot the software and power him back up again... See if that works

this one is not a color sensor ,just ir sensor.i made some video.moment

Is your IR a transmitter and receiver all in one? Is there anyway to test it separately to confirm that it is working or not working? Is it plugged in correctly? Is this your ir transmitter/receiver?

yes thats the ax-s1. in the first video you all sensors works in the manager. second video you see the real robot sees nothing.