Blackvue 750 causing 12V battery warning?

[efusco]

Recently installed a Blackvue 750 2Ch to replace my dead 650. Seems to be working great for the most part, but I did notice that it seemed to increase my phantom battery drain a couple of miles per day, but not sure as the weather is colder so hard to know where to attribute that loss.

However, this evening, I started the car and had the "12v battery needs replacement" warning. While it is entirely possible that it does need replacing, it seems a tad unlikely as it was just replaced about a year ago and my original lasted about 4 years.

I also know that the warning is triggered not by the 12v battery voltage, but by a measure of the amount of charge it is requiring from the traction battery. So if the new Blackvue is causing significant increased draw beyond what the car is programmed to expect it could trigger this.

Just looking to see if anyone else has experienced it. I'm out of warranty so the 12v replacement will be on my dime and if it isn't really necessary I sure don't want to do it...but then I have to figure out when I'll know if/when it really is needed.

Not using a Power Magic Pro, direct connection to continuous power. Am using Parking mode.

 

[LineofSight]

I have a Blackvue DR650GW. I am using the Power Magic Pro with it. My timeline:
Model S 85 delivered September 2014
Blackvue DR650GW installed - February 2015
First 12 volt battery replaced April 2017. Lasted 2 years and 7 months.
Second 12 volt battery replaced November 2017. Lasted 7 months.

I have not noticed any increase in vampire drain on my car.
I don't think my Blackvue is causing any extra strain on the 12 volt battery, especially since I try to turn off the Blackvue by turning off the Power Magic Pro when I come home. Sometimes I forget to turn it off, but the Power Magic Pro turns off the Blackvue in 6 hours even if I forget.
I don't know what caused my 12 volt battery to die so soon. Just to be clear; the 12 volt battery was replaced, under warranty both times, based only on the "12 volt battery needs service" message on the Instrument Cluster (IC).

 

[David.85D]

I have a 750 2ch and have not had a problem. Hardwired, always on. The nominal current draw is very low - at or below 1 amp.

Assuming it never goes to sleep (which it should) - thats about 280 watt-hours per day or 0.9 miles of range.

Can you measure how much current yours is drawing? Perhaps yours is using more?

Or its just a coincidence... cold kills batteries...

Mine came with a 2 amp fuse built in. If you havent disabled that, then that would limit the max drain to 1.8 miles of range per day.

 

[David.85D]

Just looked it up and “parking mode” is supposed to be 5W. Thats 120 Wh or about 1/3 mile of range per day.

 

[efusco]

I don't have any way to measure, but thank you David.85D for that info. Does seem unlikely that that small of drain would cause the computer to think that the 12v was drawing too much...but I don't know what the threshold is.

 

[ILLCOMM]

Tesla's 12V battery setup is delicate to start with: the charge/discharge cycles are insane which is why the 12V battery dies so quickly. It is factually true that any device hung onto the 12V system makes this problem worse because that device will increase charge/discharge cycles. You're asking for problems.

There is a very long, very good thread where a TMC member blog post where someone measures the behavior of the 12V system and is floored by how absurd it works. I cannot find that thread now (admittedly not trying hard), but it's worth a read for the education alone.

TL;DR: yes, the Blackvue is an input to the problem, but the core problem is Tesla's implementation.

(BTW, I have no blackvue or anything non-stock in my car at all, but my 12V battery died in 4 months and < 2,500 miles)

EDIT: here's the post I referenced above: Syonyk's Project Blog: Tesla Model S 12V Battery Analysis

 

[RandyS]

I use a CTEK battery tender when the car is in the garage to minimize 12 volt charge/discharge cycles...

 

[apacheguy]

Just looked it up and “parking mode” is supposed to be 5W. Thats 120 Wh or about 1/3 mile of range per day.

The capacity of the 12 V is very small. While 5 W doesn’t sound like much, it will increase the number of wake cycles that the vehicle will need to top up the 12 V. This will result in vampire drain much greater than 1/3 of a rated mile.

 

[David.85D]

I tried to work through syonyk’s blog post. He talks about the average drain being 30W to 40W, so the 5W could be 15% extra, but it really seems that is the average of both driving and parking.

I couldnt see where he/she said what the Tesla uses in sleep mode or if that was the value for sleep mode.

Seems like the computers and displays ought to use more than that, which left me puzzled

 

[Akikiki]

Well, you know you have to deal with the 12V replacement first and separate of the dash cam issues. But once you have let Tesla fix the 12v battery issue you might want to consider a on/off switch for the 750 to give you a warm and fuzzy that its not the problem

I've got both a 650 and a 750 installed in my S. Gives me 360 degree coverage. I lose about 2-3 miles a day in drain.
Before I added the second Blackvue, I installed a single channel remote switch I bought on Amazon for $16. Took it out of its
black case and added it between the grille and roof. This allowed me to turn the 650 off when in the garage at home.

 

[David.85D]

In the middle he/she says “If I ballpark 40W as an average, that's 80-100Wh per discharge cycle. That's only 25% of the battery capacity, so it should be good for 5000+ cycles per the spec sheet. Obviously, it's not lasting that long.”

I take this to mean the car is drawing 40W at rest, and the car is waking up every 2.5 hours (100 Wh) to charge off the main pack.
If we assume the car is parked from 6 pm to 8 am each night, that is 5.6 charge cycles per night. If you add 5W more, it cuts the recarge cycle time to 2.3 hours and 6.1 cycles per night.

Doesnt seem like a killer change, when the battery is specified to 5000 cycles at this limited discharge.

Its got to be something else. To me at least.

 

[isjka]

Is it not possible to unplug the 750 while it's parked in a garage?

 

[apacheguy]

Full sleep idle draw is much less. Less than 10 W.

 

[Akikiki]

Is it not possible to unplug the 750 while it's parked in a garage?

Wait a minute. Who does things the easy way? Why just unplug when you can wire something else and "use a REMOTE" ?

 

[David.85D]

Wait a minute. Who does things the easy way? Why just unplug when you can wire something else and "use a REMOTE" ?

These days I’m pretty sure you have to make it autonomous with a self learning Algorithm.

 

[FlyingCookie]

I've had a BlackVue DR750-2CH since last October and just finally got the 12V battery warning a few weeks ago.

The BlackVue doesn't use enough power to do any damage to anything. It does increase phantom draw, but more than likely the battery just happened to develop a bad cell around the time you installed the camera. I noticed my vampire loss go up significantly about 2 weeks before my 12V battery message came up.

With a little modification to the car, I installed a LiFePo4 battery, but that's a story for another thread

 

[AllThingsFasT]

I recently had a 2 Channel 650S installed and I'm more interested to know how it "died" on you? Could that be a linked problem?

 

[Ande]

if it's using 5W , then it's quite inefficient, and should produce some heat... I doubt those cameras are that bad, don't somebody here have proper instruments to measure the current at a given voltage ?
Also; what IS the voltage where you connect them ? - 15v ? if so, and it got a linear regulator, that would produce more heat than if it was fed with 12v or 5v.

 

[Skysurfer]

if it's using 5W , then it's quite inefficient, and should produce some heat... I doubt those cameras are that bad, don't somebody here have proper instruments to measure the current at a given voltage ?
Also; what IS the voltage where you connect them ? - 15v ? if so, and it got a linear regulator, that would produce more heat than if it was fed with 12v or 5v.

They do produce a fair bit of heat but I think most of that is from the processor doing motion detection and storage from two video signals, which is a fairly intensive task, not so much from the power regulation. They connect right to the vehicle 12v.

 

[Akikiki]

They do produce a fair bit of heat but I think most of that is from the processor doing motion detection and storage from two video signals, which is a fairly intensive task, not so much from the power regulation. They connect right to the vehicle 12v.

The 550 2CH was famous for generating a lot of heat. IT was known for failing because of the heat. And you could feel it. That improved with the 650S and the heat was less. You could feel the difference. I've not noticed a lot of heat difference (less) with the 750S.