Dashcams in Vehicle with Stop/Start Function

DT MI

Well-Known Member
Joined
Oct 10, 2014
Messages
6,735
Reaction score
5,624
Location
Michigan
Country
United States
Dash Cam
More than my wife thinks I need.
It's a slow, lazy day today so I got to thinking (which is always dangerous in my case :rolleyes:) - that plus we are considering buying a new vehicle in the next few months so I have a real world interest in this.

With the prevalence of stop/start technology in new cars increasing as a result of CAFE standards in the US (and possibility other countries as well - I don't know) I see some less-than-interesting side effects for users of dash cams.

The issue is when the vehicle automatically restarts power is usually interrupted to all accessory outlets/circuits during the restart. This short term power cycle can cause issues with dash cam function in a number of ways:

1) Cam shuts down and does not restart
2) Cam shuts down and restarts but corrupts one or more files
3) Cam shuts down and restarts normally but misses a 'few' seconds where nothing is recorded
4) Cam resets itself to factory settings (I specifically had this happen to one of mine when I turned the ignition on/off/on/off/on in a short period)
5) 'Parking mode' may be inadvertently started/stopped

Other issues could arise as well but these are the ones that come immediately to mind.

Most of these problems would likely happen with capacitor based cameras because they initiate a shutdown as soon as power is lost while, to the best of my knowledge, most battery based cameras either delay, or can be set to delay, shutdown for some period of time after loss of power and if power is restored operation continues normally.

Now for the big question - what can be done to preserve normal dash cam operation during the stop/start cycle? A few of my thoughts for openers:

1) Turn off the stop/start function in the vehicle. Downside is it's not possible with all vehicles and pretty much defeats the purpose of having it.

2) Increase the size of the capacitor to allow the camera to operate normally for some short period of time (5 seconds?) before going into shut-down mode.

3) Add a supplemental battery to capacitor based cameras. Kind of defeats the advantages of using a capacitor in the first place unless it's possible to tap into the button battery some (most?) cams have to maintain date/time.

4) Use only battery based dash cams but replace 'volatile' batteries with something more stable.

5) Power dash cams only from an 'ignition on' circuit versus 'acc' circuit. Downside to this is it would pretty much mandate hard wiring of all cams and be a major PITA with multiple cameras.

I would think that dash cam manufacturers would have a significant interest in this issue given that US market penetration is in it's infancy, and if cameras don't function reliability with the emerging auto technology it will only get worse instead of better.
 
The most successful cams will be the ones where the driver doesn't have to worry about stop-start systems or interruptions to 12v supply.
The simplest solution would be a capacitor of sufficient size that it can power the cam for 3-4 seconds without 12v supply and still have enough power to complete the shutdown, combined with firmware that ignores power interruptions less than 3-4 seconds.
It's do-able. It's already been done. Capacitor-powered @JooVuu X cam is capable (I like to think partly because I chewed Dan's ear about it) and that's why we have a handful of X-cams in our household's cars.
 
a topic that's relevant to my interests.

i'm already using a battery discharge prevention device for my current setup so i think i'd use that as well with any new car purchase. it'll give us a time delay or voltage cutoff so the start/stop function won't interfere with normal recording.
 
FWIW. I had occasion to use a vehicle with the stop-start function. As I recall there was no affect on any of the running systems during or after the stop/start. By this I mean radio/nav, wipers, hvac. I did not have anything plugged into the cigarette lighter so that may have been interrupted.
 
You'd like to think manufacturers had thought this through and minimised any power disruptions, but as previously said, the accessory socket is a prime candidate for being turned off, just in case it is taking a huge amount of current.

The problem with increasing the size of an internal capacitor is the physical size.

However, it would be a trivial matter to add an inline capacitor, or several, along the power lead. That would also act to smooth incoming power, always a good thing.

A 12V to USB 5V adapter would be an excellent place to put a massive super capacitor. I wonder if any already exist? Or if one could could be modded this way?

Sent from my SM-G903F using Tapatalk
 
FWIW. I had occasion to use a vehicle with the stop-start function. As I recall there was no affect on any of the running systems during or after the stop/start. By this I mean radio/nav, wipers, hvac. I did not have anything plugged into the cigarette lighter so that may have been interrupted.
I have such toyota and start/stop has no affect to any other electrical system, it's a standard diesel model with standard battery.
Anyhow, i didn't like that system so i disabled start/stop system permanently, i'm old scool guy and i want to be in charge (at least in my car:))
 
I have such toyota and start/stop has no affect to any other electrical system,...
I'm sure the impact of any stop/start system varies by vehicle. This is from the 2017 Toyota Highlander manual:

■When the engine restarts after having been stopped by the Stop & Start
system (if equipped)

The power outlets may be temporarily unusable, but this is not a malfunction.
 
All of my vehicles have this feature, and it has been a problem in none of them.

I don't use the fancy 12v converters / hardwire kits either, I use the cheap ones.
 
I have a RAV4 Hybrid (2016) with smart key and stop/start. No problem with my 2 Mobius. One is battery, other capacitors.
 
Huge supercaps are being made so there's no problem of availability, only size. Shouldn't be tough to design an inline cap storage bank between PS and cam, but then you'd need a very stout PS to handle the charging of those caps. Safer battery technology exists, the reason LiPo and LiIon are so popular is their high power density- lots of oomph in a very small size. NiMh is magnitudes safer, less susceptible to heat issues, and within it's limits also delivers a more constant voltage over use-time :) Would be pretty easy to integrate battery power inline, but you'd need a way to switch it out so it could charge when normal power is available plus the means to charge it properly. And all of these would require an output power voltage regulator which are also readily available at these mild current levels :D

The easiest 'fix' if needed would be to tap cam power to always-hot run through a dash-mounted switch (perhaps with an indicator light) and the user turning the switch on and off manually as needed. Half my cams are wired that way now and it's become an automatic habit now- not inconvenient at all :cool:

Stop/start may save fuel instead of idling an engine, but the stored energy being used then has to be replaced, which since no system is 100% efficient means that you're losing efficiency in one area to save it in another. And there's now accelerated wear on all the engine starting components which will need replacement much earlier than before. Those replacements must be manufactured which takes energy as does the recycling of the old dead components. So when you take a global view instead of just seeing fuel usage, stop/start wastes as much or more energy than it saves and probably pollutes more too. When fuel prices become astronomical then maybe- but for now it's just a gimmick; an answer to a question which shouldn't be asked yet :(

Phil
 
Huge supercaps are being made so there's no problem of availability, only size. Shouldn't be tough to design an inline cap storage bank between PS and cam, but then you'd need a very stout PS to handle the charging of those caps. Safer battery technology exists, the reason LiPo and LiIon are so popular is their high power density- lots of oomph in a very small size. NiMh is magnitudes safer, less susceptible to heat issues, and within it's limits also delivers a more constant voltage over use-time :) Would be pretty easy to integrate battery power inline, but you'd need a way to switch it out so it could charge when normal power is available plus the means to charge it properly. And all of these would require an output power voltage regulator which are also readily available at these mild current levels :D

The easiest 'fix' if needed would be to tap cam power to always-hot run through a dash-mounted switch (perhaps with an indicator light) and the user turning the switch on and off manually as needed. Half my cams are wired that way now and it's become an automatic habit now- not inconvenient at all...

While all these 'solutions' will work what's really needed is an 'out of the box' solution that the average Joe Six-Pack buying his first dash cam will be able to do on his own. While most members here would probably be willing to go that route the average consumer would throw his/her hands up in frustration and put the camera either in the closet or trash.

....Stop/start may save fuel instead of idling an engine, but the stored energy being used then has to be replaced, which since no system is 100% efficient means that you're losing efficiency in one area to save it in another. And there's now accelerated wear on all the engine starting components which will need replacement much earlier than before. Those replacements must be manufactured which takes energy as does the recycling of the old dead components. So when you take a global view instead of just seeing fuel usage, stop/start wastes as much or more energy than it saves and probably pollutes more too. When fuel prices become astronomical then maybe- but for now it's just a gimmick; an answer to a question which shouldn't be asked yet :(...
And that's what happens when the 'we know what is best' politicians get tunnel vision and fail to look at the big picture. :cry:
 
I never park with my engine running. I get 40mpg.

My colleagues in identical vans nearly always park with their engine running for a while. They get about 50mpg.

Of course we are in different areas with different traffic, but I can't help but think the people behind these start stop systems are doing it on principle and so they can be seen to be doing something. I don't believe they have sat down and worked out how SIGNIFICANT any fuel savings are. It's foolish to say "it must save some fuel so it must be a good idea." If it only saves 0.1% of your fuel use but has massive downsides in other areas then it's doing more harm than good.

I drive in town and it's the constant start - stopping CAUSED by traffic lights that wastes my fuel, not the piffling amount used to idle the engine.

Sent from my SM-G903F using Tapatalk
 
Vehicles with stop-start normally use AGM batteries instead of normal lead acid, partly so that they can charge up fast enough between stops and partly so that they can run for a while without any charging (improves overall efficiency). As well as charging faster they can also discharge faster so there is no need to turn off the accessories to start the engine.

I think people are trying to solve a problem that does not exist, at least on the majority of vehicles.
 
If there are no way to bypass that stop/start stuff, then i am on my last new car now.
I really think its stupid and it would drive me even more insane.

PS. same goes for fog lights coming on when turning, just looking at other cars with that drive me up the wall.
 
If there are no way to bypass that stop/start stuff, then i am on my last new car now.
I really think its stupid and it would drive me even more insane.

PS. same goes for fog lights coming on when turning, just looking at other cars with that drive me up the wall.
At least toyota has simple cure for that.
There is several security features for disabling start stop, it goes of if you pull hand brake, open dor, or open hood (bonnet), easyest way to disable it permanently is locate wire and switch under hood latch and just simpy disconnect wire connector from switch. I did it very soon and i have been driving like that for 3 years now and everything works well, car computer thinks that hood is open and start stop system never activate.
 
Last edited:
I did it very soon and i have been driving like that for 3 years now and everything works well, car computer thinks that hood is open and start stop system never activate.

that will be good if ever you're in a serious accident and they pull the data from the computer that says you were driving with the hood open :p

Edit: just to be clear, not wishing you any misfortune at all
 
and they pull the data from the computer
That's becoming commonplace now in serious cases ;) And many folks are still unaware that "Big Brother" is watching them like this. I don't think it would be a problem for Sabe who could say "No, the hood was down. I don't know why the screwy computer would say something like that. Must be a Microsoft designed computer" :ROFLMAO:

Phil
 
Maybe i do like in old joke.
I buy some dildos - not that i need them,
but to hide them in engine compartment so that safety investigators work is more interesting when they try to figure that out - what the...?!:)
 
Back
Top