Walmart LED Security light

Thread Starter

robismod

Joined Sep 22, 2015
176
Less than a year old, Walmart outside LED security light with
Motion Sensing. About 30+ LEDs. Operation is dim at dark, but brightens when motion is detected…It has just started flashing on and off, about a second each. Online searching hasn’t given me much to go on. Insides look fine, a little dampness here and there but doesn’t look like any problem. Small circuit board not much bigger than a postage stamp looks fine.
Trash or maybe something simple?
 

Yaakov

Joined Jan 27, 2019
5,476
The flashing probably indicates a failed capacitor which is oscillating. If you take apart the lamp you can try replacing any electrolytic caps on the board. This is a common failure mode, heat kills the capacitors.
 

LowQCab

Joined Nov 6, 2012
1,913
Aiming / Positioning, dirty Detector,
Tree-Branches, Bushes, etc.
Otherwise, throw it away and get a new one.
.
.
.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
Aiming / Positioning, dirty Detector,
Tree-Branches, Bushes, etc.
Otherwise, throw it away and get a new one.
.
.
.
Yes sir, that’s what the wife says…but…I almost never can do that until I at least poke around some. My trouble is knowing when to call it quits …LOL. Many times on certain things I’ll spend a lot of time researching…I think it’s good for my aging brain as it keeps me learning about many things around us. I’m starting to forget a lot, and that scares me…
 

MisterBill2

Joined Jan 23, 2018
11,556
I have a motio sensor light that does that when it gets cold, the colder it gets the more sensitive it becomes. That is because the difference between anything slightly warm and the base temperature increases.
In addition, it may be that light is getting to the day/night sensor so adding a light shield is a simple thing to try. Or just cover the daylight sesor up and see if that solves the problem.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
I brought the light inside, turned it off for a while. I put the solar panel under a light for the night, then tried again. It turned on, but shortly started the off/on/off/on pattern.
 

MisterBill2

Joined Jan 23, 2018
11,556
Try changing the mode to off/on, with no dim. And now I learn that it is battery power with solar panel charging.
So try it with a power supply holding the battery voltage constant, and the solar panel disconnected. The symptom is feedback, but from what to what? That is why I suggest removing the solar panel for a bit.
 
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Thread Starter

robismod

Joined Sep 22, 2015
176
Try changing the mode to off/on, with no dim. And now I learn that it is battery power with solar panel charging.
So try it wit a power supply holding the battery voltage constant, and the solar panel disconnected. The symptom is feedback, but from what to what? That is why I suggest removing the solar panel for a bit.
Sounds good…I’ll give that a try in the next couple of days (provided we’re not knee-deep in snow haha)…
Thanks again.
 

MisterBill2

Joined Jan 23, 2018
11,556
With my mains powered motion sensor light, when there is bright reflective snow, I have had it start to oscilate some times, if the sky is clear. The light level somehow triggers that day/night sensor and then when the lights come on it sees to much light and switches off. But only when it is really cold.
It certainly seems that extreme cold increases the sensitivity quite a bit.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
With my mains powered motion sensor light, when there is bright reflective snow, I have had it start to oscilate some times, if the sky is clear. The light level somehow triggers that day/night sensor and then when the lights come on it sees to much light and switches off. But only when it is really cold.
It certainly seems that extreme cold increases the sensitivity quite a bit.
Hmmm…thinking back on it, we had a good bit of snow but the night it started acting up most was melted. It was about 35ish outside but we were burning some paper/cardboard in a small fire pit about 20 feet away. The light is mounted above the door of a22’ truck delivery box…
 

MisterBill2

Joined Jan 23, 2018
11,556
Hmmm…thinking back on it, we had a good bit of snow but the night it started acting up most was melted. It was about 35ish outside but we were burning some paper/cardboard in a small fire pit about 20 feet away. The light is mounted above the door of a22’ truck delivery box…
There could be some smoke deposit on one or more surfaces altering the optical behavior. OR the smoke could have reduced the output of the solar array and cause a low battery voltage problem. A bit of cleaning could be all it takes. OR it may be something else completely.At this distance it is guesses based on my experience, "your results may differ", to use some ancient weasel words.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
There could be some smoke deposit on one or more surfaces altering the optical behavior. OR the smoke could have reduced the output of the solar array and cause a low battery voltage problem. A bit of cleaning could be all it takes. OR it may be something else completely.At this distance it is guesses based on my experience, "your results may differ", to use some ancient weasel words.
I’ve cleaned, dried, massaged (kidding LoL) about anything I think that could be done…it will start up sort of normally (after being turned off and set in light for overnight) but within a few minutes it’s back to the flashing routine.
 

MisterBill2

Joined Jan 23, 2018
11,556
Are you able to easily measure the battery voltage?If that is cycling along with the flash, then the problem is obvious. If not, more research needed. And it does sound a bit like the battery voltage dropping then the lEDs switch off then the battery voltage recovers until the LEDs witch back on. That is a believable guess, monitoring the voltage will verify if right or wrong.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
Are you able to easily measure the battery voltage?If that is cycling along with the flash, then the problem is obvious. If not, more research needed. And it does sound a bit like the battery voltage dropping then the lEDs switch off then the battery voltage recovers until the LEDs witch back on. That is a believable guess, monitoring the voltage will verify if right or wrong.
Thanks for all your suggestions. I tried several things to no avail, but ended up gutting it. It’s cheap so I can get another one if need be. I got to looking outside a bit ago, and realized the area is pretty well covered by additional lighting I had put up recently. So, now I’ve run a straight wall wart to the light panel, giving me an extra work light I can use.
I did check the battery outside the unit—it showed almost 3 volts, and direct to the light panel lit it fine. The solar panel was putting out just under 5 volts, but after a couple minutes dropped down to around 1-2 volts.
 

Thread Starter

robismod

Joined Sep 22, 2015
176
OK, it seems then that the problem was/is battery voltage dropping. That certainly does happen as rechargable batteries age.
Odd thing is, this unit wasn’t even a year old. I have a couple others that are still going strong…
I didn’t test the battery very well—maybe I’ll stick a load on it and see how it reacts for a while…but…the solar panel—I left a meter on it while it was facing a bright light, and the output went from near 5 volts to down around 1-2 volts and hovered there a bit…is that a normal action?
 

MisterBill2

Joined Jan 23, 2018
11,556
Odd thing is, this unit wasn’t even a year old. I have a couple others that are still going strong…
I didn’t test the battery very well—maybe I’ll stick a load on it and see how it reacts for a while…but…the solar panel—I left a meter on it while it was facing a bright light, and the output went from near 5 volts to down around 1-2 volts and hovered there a bit…is that a normal action?
It does not seem like a normal action at all, especially if just feeding a meter. Was there any chance that it over heated because of the light being close? Heat is about the only thing I can imagine causing a problem. Unless there is a voltage breakdown at some sort of shorted circuit. Or bugs moving around inside??
 

Thread Starter

robismod

Joined Sep 22, 2015
176
It does not seem like a normal action at all, especially if just feeding a meter. Was there any chance that it over heated because of the light being close? Heat is about the only thing I can imagine causing a problem. Unless there is a voltage breakdown at some sort of shorted circuit. Or bugs moving around inside??
I don’t believe the panel overheated, but the small circuit board inside had a burnt smell, but no visible signs. All clean inside the unit, other than there was some very slight moisture around…didn’t see any on the board or near, but a little more between the LEDs and outer clear plastic panel. A couple of the LEDs had burnt out…
 

MisterBill2

Joined Jan 23, 2018
11,556
Some high output LEDs appear to have a failure mode that causes flashing, before they fail more completely. And one failed LED will disrupt the whole series string.
 
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