Solved - Capacitor Getting Weak, Causing No Start??

Skeezix

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Dash Cam
Viofo A119
I bought my A119 in January of 2017 and have run it in my truck since then without problems. I have it hard-wired to the ignition terminal. I don't drive too much, so the truck stays in the garage sometimes for a couple of weeks at a time.

Earlier this year (2019) the A119 sometimes would not automatically start when I turned the key to IGN. I had to press its power button and then it would start, and the problem would not repeat unless I stored the truck for around 2 weeks.

Two weeks agowhen I started out on on a long trip the A119 again would not automatically start. This time, however, when I pushed the power button it would start, flash the screen with camera video for maybe 1/10 second, and then turn itself off. After pushing the power button several times and getting the same response, it finally restarted and stayed on.

So I took my trip and had no problems with the A119 except for the last morning. It would not start no matter what I did. The previous night the ambient temperature was around 40F so I thought maybe it was too cold (it's been colder and it started w/o problems). For next two hours while driving I tried to start it using the power button but was not successful. After driving for about 2 1/2 hours however, it finally did start and then ran without problems.

Has anybody else on this forum had similar problems?

I'm thinking that the capacitor is getting weak and I would like to replace it. Can somebody tell me the specifications of the capacitor (mf, voltage, temperature range, etc.) and where I can get one?
 
2.7v 3.3f and it takes two of them. There is also a very small rechargeable button type battery that needs to be checked as well. The capacitors are available at eBay but be aware of many fake products in there. Maybe mouser electronics would be a place to check as well
 
I would test the camera with the 12V car adapter and Viofo power cable first.

Do you get any corrupt files on the card?
 
Thank you for the link. I read the spec sheet and saw that the capacitance was 3 farads. When I downloaded the PDF showing the full specs, I saw other capacitors rated at 350 and at 500 farads.

I received my initial training in electronics from the U.S. Army back in 1966. At that time, I was told that a capacitor with a one farad capacity would be huge and thus completely impractical. What has changed to allow such a small capacitor to hold such a large charge???
 
2.7v 3.3f and it takes two of them. There is also a very small rechargeable button type battery that needs to be checked as well. The capacitors are available at eBay but be aware of many fake products in there. Maybe mouser electronics would be a place to check as well

I didn't know there was a battery in the A119. How does one check it? What's its voltage? Can it be checked in-circuit? Does Illinois sell individual caps? I live in a small town on the western slope in Colorado, and there are no electronics stores that carry that particular capacitor. MOF there are no electronic stores anywhere unless I drive to Salt Lake or Denver :(

I forgot to mention in my first post... After driving steadily for 2 hours I stopped under a bridge. When I started the engine about 1/2 hour later, the dashcam came on automatically. And when I gassed up at the end of the trip, it came on automatically.
 
I would test the camera with the 12V car adapter and Viofo power cable first.

Do you get any corrupt files on the card?

I'll test the camera with the car adapter after the truck sits for a couple of weeks.

All of the files on the card are good.
 
I don’t understand them very well either as I have see 3 farad capacitors that are huge and they where used in car audio but this smaller ones are called “super capacitors”. I know they have changed the chemistry design that allows more power in a smaller package but still I don’t think the compare at all the energy they hold as the ones used in car audio could make huge sparks if the two poles where shorted together.
As for the technical part, maybe one of the more experienced guys here in the forums can help us to understand better. That being said, have you opened the camera yet and done some testing on the capacitors to see if the look bulged and or retaining voltage? Also like CaptureYour action has suggested, using another USB adapter and charger to rule out that one is going bad.
 
I didn't know there was a battery in the A119. How does one check it? What's its voltage? Can it be checked in-circuit? Does Illinois sell individual caps? I live in a small town on the western slope in Colorado, and there are no electronics stores that carry that particular capacitor. MOF there are no electronic stores anywhere unless I drive to Salt Lake or Denver :(

I forgot to mention in my first post... After driving steadily for 2 hours I stopped under a bridge. When I started the engine about 1/2 hour later, the dashcam came on automatically. And when I gassed up at the end of the trip, it came on automatically.
I wish I could be of more help to you right now and give you more accurate information about the other smaller battery I mentioned earlier. Actually I’m thinking is another capacitor that looks just like one those batteries used in hearing aids and my understanding is the one responsible to retain date and time in the camera .
Those capacitors you won’t be able to find them on a regular electronic store and more than likely will have to be ordered through the website I sent you earlier (mouser electronics) eBay or Amazon. If you can determine the caps are the culprit after testing them just make sure you measure the length and diameter plus double check that yours are also 2.7v 3.3f
 
I'll test the camera with the car adapter after the truck sits for a couple of weeks.

All of the files on the card are good.
If you have no corrupt files, then the caps are probably fine. A bad capacitor will usually corrupt at least the last file of every drive.
 
If you have no corrupt files, then the caps are probably fine. A bad capacitor will usually corrupt at least the last file of every drive.
Agreed, if there are no corrupted files then the capacitors are fine.

Since it appears to be temperature related, it is likely to be a bad connection, possibly in the power lead, but maybe more likely in one of the internal connectors such as the screen or image sensor ribbon cables. Unplugging and replugging these may solve the issue, but make sure you understand how to use the connectors - they require no force.

I know they have changed the chemistry design that allows more power in a smaller package but still I don’t think the compare at all the energy they hold as the ones used in car audio could make huge sparks if the two poles where shorted together.
The super-capacitors used in the A119 can also create big sparks, shorting them when full is a bad idea, the amount of energy stored is measured in Farads, so the capacity does directly compare, the only difference may be the rate at which the energy can be extracted, but people do use super-capacitors to spot weld metal together, the 100F ones are capable of starting a V8 car engine.
 
Agreed, if there are no corrupted files then the capacitors are fine.

Since it appears to be temperature related, it is likely to be a bad connection, possibly in the power lead, but maybe more likely in one of the internal connectors such as the screen or image sensor ribbon cables. Unplugging and replugging these may solve the issue, but make sure you understand how to use the connectors - they require no force.


The super-capacitors used in the A119 can also create big sparks, shorting them when full is a bad idea, the amount of energy stored is measured in Farads, so the capacity does directly compare, the only difference may be the rate at which the energy can be extracted, but people do use super-capacitors to spot weld metal together, the 100F ones are capable of starting a V8 car engine.
I haven't experimented with one of the small ones yet:geek:. I have seen videos of people using super capacitors to make battery banks for cars and few other things as well. It is a good thing NOT to attempt to discharge one of them like a regular capacitor by placing a screwdriver across or damage can occur.
 
I think the problem was a fluke. After the first start-up failure I did not turn the key off, I just pressed the Power button. When I did turn the key off and back on about 2 hours later, the A119 powered up as usual.

I'll be sure to wait a bit between IGN On and START.
 
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It is a good thing NOT to attempt to discharge one of them like a regular capacitor by placing a screwdriver across or damage can occur.
Probably only damage to the screwdriver!

 
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