ir sensor module!!!

i bought an ir sensor module which has a ir led as transmitter and a tsop as reciever...when i power it with a vcc of 5v, the output reads as 4.8v...but the problem is the output doesnt change on seeing an obstacle...can some1 suggest me a possible solution...how can i check whether the ir led is giving signal or not??

The TSOP should be active low. Hook an LED up to the output and ground, should be on normally, point a TV/VCR remote at it, press a button. The LED should flash.

To check the IR emitter, use a digital camera. Dark room helps, probably not too bright. Do you have a data sheet? The TSOP needs a signal around 38kHz. So your IR emitter needs to sending that out, not constant on.

You don't give much for details, so you want get much more than guesses...