Need help with an infra-red sensor component not detecting anything

JUST TO BE CLEAR, This was working perfectly a couple weeks ago when i first tested it. But now nothing does.

I have these obstacle avoidance sensors (http://henrysbench.capnfatz.com/henrys-bench/arduino-sensors-and-input/arduino-ir-obstacle-sensor-tutorial-and-manual/) to use as simple counters for my project.

However, i am unable to trigger the sensor AT ALL now. I have 7 of the things and none of them work anymore and i cant find the problem. Ive bent the OUT pin so that i could just plug the 5v and the GND straight into the board and used an alligator clip to connect the OUT to the right pin. But the light on the sensor is apparently saying there is always something infront of it. I have tried it with an arduino mega and an uno and nothing works.

I am thankful for any help whatsoever! ( and i hope i posted this in the right place)

Hi, Welcome to the forum.

Please read the first post in any forum entitled how to use this forum. http://forum.arduino.cc/index.php/topic,148850.0.html

This is your device. |500x208 So the power LED is ON and so is the Obstacle LED?

Have you tried adjusting the distance adjustment.

Use the camera on your phone or a digital camera and see if the IR Emitter is glowing.

Do you have a DMM?

Tom... :)

As TomGeorge asks:

TomGeorge: So the power LED is ON and so is the Obstacle LED?

Check this with only the GND and +5V connected, leave the 'Out' pin unconnected.

Yours, TonyWilk

Ok, it works now but it doesnt. For some reason it keeps detecting random things around the house. I dont know weather its because its a cheap sensor or what. I spent half an hour just walking around the house and it will detect something in a 90 degree arc infront of it seemingly randomly. the only consistent things it picks up is something about a meter to the right of the TV (which it picks up from over 15+ meters) and what I assume is the Wifi router (from about 6 meters away (which is why it was stuck on in the first place)), and the west wall of the bathroom. Other than that it just detects something, I walk towards the area and it disappears. The only things I think it could be is possibly wiring in the wall or maybe IR from the sun heating up the walls. (I honestly dont know if this is possible, but it was 44C here today)

TonyWilk: As TomGeorge asks: Check this with only the GND and +5V connected, leave the 'Out' pin unconnected.

Yours, TonyWilk

The out pin was disconnected, the obstacle LED should light up when the receiver detects something and it was constantly on. But I figured out this was due to me testing it near the Wifi router

Just shooting in the dark here about what could go wrong. Not saying any of these apply:

How much sunlight was in the room? It's IR-heavy and that reflects.

In a darkened room or closet, see if the thing says it detects after you cover the IR emitter.

Is the emitter or detector bent towards the other?

Can you put a short piece of opaque tube on the detector, even rolled up paper with tape?

Your device can only detect objects with a perfect (flat, properly adjusted, IR reflecting...) surface. If no such object is available, and the sensitivity is increased, the sensor will catch reflections from every surface in the room.

Eventually you can get some meaningful signal with the opaque tubes on both sender and receiver, else you better dump that device.

A bag of IR detectors might run about 5 cents each. IR leds are cheaper. Arduino only needs 1 of each to reflect or beam-break, and no black box to puzzle over.