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I went to start my one month old XSE this morning and it had no power. The lights, door locks, dash display...nothing worked. I did get tint on all my windows last week and the tint shop had to jump start the car after installation because it died there too, but it seemed to work fine the whole week after that. I also only had 20 miles of fuel left when I parked it in my driveway last night, but there’s no way it could have died because of low fuel right?

Meanwhile, I called the roadside assistance for a jump, so I’ll see if that works. This is weird for a new car. Anyone else experience something like this?
 

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Sounds like it may have a defective 12V battery, a loose connection or a component that's draining the battery.
 

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Sounds like it may have a defective 12V battery, a loose connection or a component that's draining the battery.
Interesting...I do have a dashcam that’s hardwired in. It’s been there the whole time and I drove over 3000 miles without an issue until it died when they were installing tint. They left the car on for two hours so I’m wondering if the battery became weakened after that
 

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Depends how you have your camera wired. If it's wired always hot, would be safe to say that you've killed the battery from the constant discharges. If it's standard FLA, those batteries don't like getting discharged--they're meant as starter batteries that are recharged quickly after a starting event, not for slow and constant discharges from a dashcam.

I've seen a lot of 12v failures in the last three years across a number of makes, so a defective battery on its own wouldn't shock me much either.
 

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The camera specs should state how much current it draws. Do you have that number?

EDIT: I pulled up a couple random dash cams on Amazon. The specs say they draw 1-2 Amps. That’s a lot of current! A small car battery can’t handle that load for a sustained period. You’d be lucky to get more than 12 hours out of it. Then every time that battery goes completely flat, it will lose some of its total capacity. Car batteries do not like being repeatedly deeply discharged.

If you know the current draw of the camera, you can use the linked calculator to size the battery you’d need to run the camera for a length of time, like say 12 hours:

 

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The camera specs should state how much current it draws. Do you have that number?

EDIT: I pulled up a couple random dash cams on Amazon. The specs say they draw 1-2 Amps. That’s a lot of current! A small car battery can’t handle that load for a sustained period. You’d be lucky to get more than 12 hours out of it. Then every time that battery goes completely flat, it will lose some of its total capacity. Car batteries do not like being repeatedly deeply discharged.

If you know the current draw of the camera, you can use the linked calculator to size the battery you’d need to run the camera for a length of time, like say 12 hours:

I seriosly doubt any of them are pulling an amp. These things are tiny, all solid state devices - they would catch on fire trying to sink that much current. I have a cheap black box camera which is very popular on amazon. It runs on a 300mA battery at 3.7V (I looked), and plugging it in charges the battery. It will run for hours without being plugged in, so even assuming current loss from charging - I think your still in a few hundred mA range at most.

My vote is as mentioned earlier - a bad starter battery, or component.
 

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I’ve read two other dead battery/new car posts on other forums this month and they both ended with “recently hardwired a dashcam but I don’t think that could be the problem”.


Any constant draw on the battery like that can eventually wear it down to the point it doesn’t want to do what it’s supposed to. I have a friend who used to need constant jumps anytime he let his car sit for more than a few days because his radio was wired wrong and slowly leached current and if he wasn’t driving enough, the battery wasn’t getting recharged enough.

If you are driving a lot it can take longer to notice the problem.
 

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Just an FYI for those that aren't familiar with the Hybrid Synergy Drive system, the 12 volt auxiliary battery isn't a conventional starting battery, it's a tiny ~40AH AGM battery that supplies power to electronics and HSD system which enables motor generator 1 to start the ICE with power from the HV traction battery, so either the 12V battery is bad, or being drained by a component, if the charging system wasn't working properly, there would be a warning light of some sort I would expect.
 

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Just an FYI for those that aren't familiar with the Hybrid Synergy Drive system, the 12 volt auxiliary battery isn't a conventional starting battery, it's a tiny ~40AH AGM battery that supplies power to electronics and HSD system which enables motor generator 1 to start the ICE with power from the HV traction battery, so either the 12V battery is bad, or being drained by a component, if the charging system wasn't working properly, there would be a warning light of some sort I would expect.
Just out of curiosity, is this "tiny ~40AH AGM battery" the battery that some are connecting their trailer wire harness to?
 

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Just out of curiosity, is this "tiny ~40AH AGM battery" the battery that some are connecting their trailer wire harness to?
Yes, many did on the 4th gen, it didn't seem to be a problem just for lights as long as the vehicle ignition is on so the ICE can start and charge it, many use the 12V as a source for emergency/camping generator with a 12V inverter, lots of discussions on it in the 4th gen HV forum as well as the web.

 

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I seriosly doubt any of them are pulling an amp. These things are tiny, all solid state devices - they would catch on fire trying to sink that much current. I have a cheap black box camera which is very popular on amazon. It runs on a 300mA battery at 3.7V (I looked), and plugging it in charges the battery. It will run for hours without being plugged in, so even assuming current loss from charging - I think your still in a few hundred mA range at most.

My vote is as mentioned earlier - a bad starter battery, or component.
Well if we use your 300mA figure, that battery calculator says you need a 16AH battery to run that device for 24 hours. That's 40% of the Rav4 hybrid's 40AH 12V battery capacity. That doesn't include the rest of the load on the battery.

If you hook up a dash cam and suddenly the 12V battery is going dead, the most likely suspect is the dash cam. Just sayin'.
 

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Well if we use your 300mA figure, that battery calculator says you need a 16AH battery to run that device for 24 hours. That's 40% of the Rav4 hybrid's 40AH 12V battery capacity. That doesn't include the rest of the load on the battery.

If you hook up a dash cam and suddenly the 12V battery is going dead, the most likely suspect is the dash cam. Just sayin'.
Is there some Lo-Voltage cutoff,
like 11.5 volts for the dashcam's????
 

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Is there some Lo-Voltage cutoff,
like 11.5 volts for the dashcam's????

Yes. In fact in one of the threads I mentioned (on the CX-5 Reddit) the guy was questioning why that wasn’t a sufficient safety measure but I think that still allows the battery to be drained below a point where it can still perform its expected tasks.
 

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Discussion Starter #14
Thanks for the replies guys. So after getting it jumped and driving to the dealer, they claimed the battery was fine and won’t be replaced under warranty since they couldn’t replicate the problem. They did say that the little light in the trunk was left in the “on” position which might have drained the battery. I’ve kept that little light on since I bought it a month ago, and it auto turns off when the trunk closes so I don’t think that’s true.

The dash cam I have is a Thinkware F800 Pro. I have it hardwired into the fuse box under the dash into the 10A fuse spot for the horn. The camera actually uses an extra battery for the parking mode, which I installed under the seat. Maybe I’ll move this to another fuse just in case. In the meantime, hopefully the car doesn’t die again.
 

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The specs for the Thinkware F800 Pro say it uses either 4.2 Watts or 2.9 Watts depending on operating mode. 4.2 Watts @ 12VDC is 350 milliamps. 0.35 Amps. That’s not insignificant.
 

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Just an FYI for those that aren't familiar with the Hybrid Synergy Drive system, the 12 volt auxiliary battery isn't a conventional starting battery, it's a tiny ~40AH AGM battery that supplies power to electronics and HSD system which enables motor generator 1 to start the ICE with power from the HV traction battery, so either the 12V battery is bad, or being drained by a component, if the charging system wasn't working properly, there would be a warning light of some sort I would expect.
Thanks for the education. I like my gas powered rav more and more every day :)
 

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Did the problem occur before the tint job or just after?
Tint application involves use of soapy water on the inside of the windows and it can run down and short out electronics.

This happened on my wife’s CX5 and we had to have everything in one fuse box dried and cleaned later. Was dead as a door nail.


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