QTR-8RC Sensor LED

Hi everyone, I'm trying to make a line follower, and using QTR-8RC sensor http://www.pololu.com/docs/pdf/0J12/QTR-8x.pdf

I wonder if anyone else know this sensor, the LEDs on the sensor aren't working, basically, I want to do the same thing as the link below http://www.youtube.com/watch?v=ZQnrEd-IFV8

I read the library for this sensor, and tried some functions, but doesn't look like working, I just need to turn on the LEDs all the time.

How is your wiring? Have you activated LEDON?

How do I activate LEDON? The sensor is working, I'm getting values from it. For LED part, I tried to connect it to a digital pin, then set it to HIGH, but nothing happened.

You still haven't shown your wiring. Do you power with 5V or 3V3?

LEDON has a pull-up on the board so LEDs should be on by default and can be switched off by connecting LEDON to GND.

BTW: How have you checked that the LEDs are not working? Remember, they are IR LEDs so your eye won't see them. Take your cell phone's camera and make a picture (not a DSLR), there you may see them.

so I won't be able to see the light? Then how come in the video, we can see it? I took a few photo too, still can't see it. basically, I just want the lights on.

You won't be able to see the light. Grab your TV remote and press a few buttons while looking at the front if you want further proof that IR is not visible to the human eye.

More expensive cameras will filter out the IR so pictures render with a color similar to what you see.