Faulty capacitor/s?

Q

Quickeze

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Before I decide to remove these for testing from the board, I wanted to get an opinion on whether these appear to be faulty based on the attached image.

The one on the right looks a little sus, but I don't know if light casing cracks are normal.

My Viofo a129 duo has suddenly died after 4 years. I think the Aussie heat might have cooked it one too many times recently 🙂

20241217_171835(0).webp
 
Quickeze said:
Before I decide to remove these for testing from the board, I wanted to get an opinion on whether these appear to be faulty based on the attached image.

The one on the right looks a little sus, but I don't know if light casing cracks are normal.

My Viofo a129 duo has suddenly died after 4 years. I think the Aussie heat might have cooked it one too many times recently 🙂

View attachment 75920
Click to expand...
It looks like the sheath has cracked at the very least from heat I'm guessing.

I can't tell from the photo but is the one on the right leaking?

when you say died do you mean it doesn't start at all?

Is there a dead short across the caps?

While you're at it consider replacing the button batteries.
 
Yeah capacitors are not the final solution, but still a whole lot better than batteries.

On the + side, today's dashcams are a lot better than the old A129, personally 4 years is about what i would expect to get out of a dashcam.
 
Sorry, can't really get a good picture in there as yet .They really don't seem to be leaking.

I noticed via saved footage it stopped working about a week ago, so I tested it with a spare sd card.

At first it came on. By 'on' I mean the rec light and mic light came on but the led display was just a green colour and it stayed that color until i removed power cord.

When I reconnected power again and tried to start nothing happened at all. No red led or anything on the screen.

How do I test for a dead short? Can capacitors only be tested when removed from pcb? Forgive my ignorance.

Is the button battery soldered in?

Thx
 
Quickeze said:
Close up doesn't appear to show leakage
View attachment 75921
Click to expand...
Ok no leakage.
On the other end are they bulging?

Using a multimeter on ohms and the probes on the legs of each cap while still in cct should give a resistive reading. Another way is put the dmm into continuity mode and see if the meter buzzes. Zero ohms or buzzing Mary indicate a short.

The button batteries do require soldering.
The capacitors will also require soldering if changed.

Ideally you are proficient with electronics or really eager to learn.

Before you pull it apart make sure it's not something else causing the failure.
Try a different power supply.
New cables or at least check they aren't loose or worn.
Check the ribbon cables are seated fully.
Smell the unit, if it smells like burnt toast then something else has failed.
 
The other ends aren't bulging.

Tried a phone charger (same one I tested it with when first purchased), didn't work. In saying that the record button led came on for about 1 sec. Never worked again after that using phone charger.

Tested on ohms with probes and resulted in a -OL for both capacitors. Continuity was buzzing for both (1.195)

Unit doesn't smell at all, no other signs of overheating or burning.

I'll look at getting a battery and a couple of caps then see where I go from there.

Thankyou very much for your help thus far. Greatly appreciated.


20241217_210421.webp
 
Quickeze said:
I'll look at getting a battery and a couple of caps then see where I go from there.
Click to expand...
They look fine to me. You can also test the capacitors by plugging the camera in, so that they charge, then unplugging it. Some of the charge will be used for shutdown, the rest should stay, slightly declining to zero over about a week. You measure the charge using the DC volts on the multimeter, should be about 2.5V fully charged across each capacitor, and still over 2V after shutdown.

Since the camera is not working, it may not shutdown, and the charge may disappear over a minute or two.
If the capacitors are faulty, you will probably get more than 2.5V across one and less across the other, if they are shorted then there will be zero volts across them, either way they need replacing, if they both hold roughly the same charge, then they are probably fine and there is no point in replacing them.

If you do replace them, unless you are an expert solderer, it is a lot safer to leave the old legs soldered to the PCB, and solder the new legs to the old legs. The old legs could do with a clean first, maybe sandpapered but don't get the dust on the PCB.


You could try a firmware install, we don't often see that needed, but it is a possibility.

You can also try disconnecting all the cables and reconnecting them, especially the ribbon cables, make sure you know how to use/release the connectors though, and try one thing at a time, then test.
 
There is a better chance you have lost the voltage regulators on the power input, in my opinion. Caps look "iffy OK" but I don't think they are in-line in such a fashion they would prevent start up. Should be sitting on the side on a charge bus and provides power to the board via an IC that actuates on loss of input power.

The battery is likely tack welded in and will be a nuisance to remove, but you should check the voltage anyway. You may be able to remove the tab on the battery by going underneath it with a sharp edged razor and slowly working at it. It is a small weld so usually goes well. If putting a new battery back in, you want to 'hit and get' with the heat and solder. Hang around too long and the heat from the soldering iron will degrade the battery. This is one of the places where manufacturers need to use holders and not solder.

Check the ribbion cable from the lens to the board, if the cable is not correctly seated in the board, the camera will not boot.
 
I should add, the main reason to try and keep this cam going is so I don't have to rewire the car again after buying a new model with new cables/harnesses, took me all day but I did it right.
 
Quickeze said:
I should add, the main reason to try and keep this cam going is so I don't have to rewire the car again after buying a new model with new cables/harnesses, took me all day but I did it right.
Click to expand...

Definitely some cars are a bigger nuisance to wire than others. Did you find what the problem was? My A229 Pro will power up and run without the super capacitor on the board, however on power down it does shut down immediately and that of course closes the video file in a very rude manner. 🙂
 
lufa6977 said:
Definitely some cars are a bigger nuisance to wire than others. Did you find what the problem was? My A229 Pro will power up and run without the super capacitor on the board, however on power down it does shut down immediately and that of course closes the video file in a very rude manner. 🙂
Click to expand...

Been a busy time for me, sorry for the update delay. I think you are probably correct with the problem being elsewhere, It just didn't feel worth spending lots of time on this project.

After testing both capacitors and button battery they both appeared to be fine. Battery was reading 2.95 volts from memory and is tack welded on both sides which would have been a pain for me at least to try and remove and replace correctly. Capacitors were both reading the same. Was really hoping it was the capacitors which would have been an easy replacement for me to do.

I've decided at this time it would be simpler to buy a replacement cam (A129 Plus Duo) which would just be a swap over. I currently have the A129 Duo set up with a hardwire kit and celllink neo and would just need the rear cam cable updated/replaced from what I've read, which is a pain but better than rewiring the front again and I can just use the existing celllink battery.

Curiosty will probably prompt me to take another look at the faulty cam again one day when I have more time and can research a bit more on testing very small components.
 
The A129 is a fine camera. I have the main A129 camera mounted to my back hatch and it works fine there. Too many folks get caught up in having the latest model but anything from the A129 to the A329 will do fine.
 
The Viofo A129 duo was my main dashcam for years and the only reason I've removed it is because i ran out of windscreen space for testing other models.
The newer A129 models increased resolution keeping them in the sweet spot for improved image quality.
 
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