Sensor Switch and Light, unusual behavior

[Dante99]

My light connected to a sensor switch(on/off motion detector and day night detector) stopped working about 6 weeks ago.  The light never came on at night when there was motion in front of the sensor.  Then 3 nights ago it came on when I drove in and since then it has worked normally.

 

What would cause it to stop working for 6 weeks then without any repair or adjustment, just start working again?

 

The switch is a standard unit sold at Home Pro and all around, the light is an LED tube unit.

[flyingtlger]

Clean the sensor.....

[Dante99]

5 minutes ago, flyingtlger said:

Clean the sensor.....

Thanks.  I cleaned the outside of the sensor as soon as it stopped working, about 6 weeks ago.

 

[Korat Kiwi]

Hopefully Crossey will be along soon to give an informative reply. 

 

Sensors do wear out.  Sometimes insects get caught in them and block the sensor as well. 

 

Depending on model you maybe able to just replace the sensor or have a spare one on hand for when your one finally dies. 

[worgeordie]

If its a PIR switch maybe the heat of the car was enough to switch it on

and it's been OK since. 

 

reards worgeordie

[sometimewoodworker]

A common problem with electrics and electronics are insects usually ants. So a disassembly and cleaning is often the cure. It is possible that desiccation of corpses could have allowed the switch to function again.

[Dante99]

Thank you very much gentlemen.  When I get a chance, I will open it up and clean the inside, then put a moth ball in it before closing.

16 hours ago, sometimewoodworker said:

It is possible that desiccation of corpses could have allowed the switch to function again.

Yes, could be. Or other critters moving about relocating some corpses?   

[sometimewoodworker]

48 minutes ago, Dante99 said:

Thank you very much gentlemen.  When I get a chance, I will open it up and clean the inside, then put a moth ball in it before closing.

Yes, could be. Or other critters moving about relocating some corpses?   

The mothball is not a good idea as the volatiles could well attack the circuitry and components. What works is the ant powder. I now add some to virtually all light fittings and sockets and its lasts forever, the mothballs will need to be replaced, probably annually. Not to mention that the mothballs are large.

Edited March 4 by sometimewoodworker

[Muhendis]

Be very careful when handling the plastic detraction cover, that's the white cover over the front of the sensor. 

 

It is very brittle and is made more so if in direct sunlight.

 

I have four of these things around my house and they all, except one, stopped working after a short time.

[Dante99]

 

Mine looks like this and I have had to change it only once or twice in 14 years.

[Muhendis]

23 hours ago, Korat Kiwi said:

Sensors do wear out.  Sometimes insects get caught in them and block the sensor as well. 

 

Depending on model you maybe able to just replace the sensor or have a spare one on hand for when your one finally dies. 

Sensors do wear out with time but we are talking centuries rather than weeks. 

 

Insects don't really get caught in them but they can, as Onetimewoodwoker has said, trigger the sensor and they can block the sensor if they can get into the electronics.

 

Further reading on how things work is here:

https://robocraze.com/blogs/post/pir-sensor-working-principle#:~:text=It utilizes a special type,and triggers the sensor's alarm.

 

Regarding effect of mothballs on electronics. Naphthalene (mothballs) is a hydrocarbon and has no effect on electronic components or wires but as Onetimewoodwoker has said, they are big and unlikely to fit into the sensor casing.

 

I like the idea of ant powder. That's now on my todo list.

[bluejets]

Most likely a kactus led bulb.

If all else fails, replace the wholus bolus.

After all, I'm certain you would have seen " no servicable items inside".

Edited March 5 by bluejets

[sirineou]

On 3/3/2024 at 11:14 AM, Dante99 said:

What would cause it to stop working for 6 weeks then without any repair or adjustment, just start working again?

Perhaps the gecko who had told his friend they would meet in front of your motion sensor, got tired of waiting and moved. Personally I think it was a case of miscommunication , and his friend were waiting at a different motion sensor, 

Did you also have issues with a different sensor? 

[Dante99]

Two days ago it stopped working again.

[Crossy]

I think it's dead Jim!

 

Take the beast apart, check all the soldered joints, if feeling enthusiastic replace any electrolytic capacitors.

 

Alternatively buy a new one.

 

 

 

[Dante99]

On 3/6/2024 at 7:55 AM, Crossy said:

Alternatively buy a new one.

will do, thanks

[Mike Lister]

Thread closed, per OP request.

[CharlieH]

Requested closure by OP.

 

//CLOSED