YET ANOTHER 12V battery fail thread

[Steve A.]

R1S w/12xxx VIN 25,291 miles and 174 miles to empty delivered 6/16/2923. SMH


Explain to me again why I got ZERO warnings beforehand and why the battery pack can't charge the 12V battery?

Sponsored

 

[d15b7]

Hi there. I can’t comment on why no 12v warning before the battery died. But I can try to help with the second part of your question: you need a charged 12v battery power to activate the contactors on the high voltage battery pack to allow the DC to DC converter be able to recharge the 12v battery. It’s a little like a catch 22; you need 12v battery to be able to ‘turn on’ the high voltage pack to in turn be able to charge the 12v battery.

you should be able to recharge the 12v battery manually from the wire pigtail which is located under the rear hitch cover. Once it’s recharged (assuming it isn’t totally dead/not useable at all) you should be able to start up your Rivian. Good luck!

 

[Steve A.]

Hi there. I can’t comment on why no 12v warning before the battery died. But I can try to help with the second part of your question: you need a charged 12v battery power to activate the contactors on the high voltage battery pack to allow the DC to DC converter be able to recharge the 12v battery. It’s a little like a catch 22; you need 12v battery to be able to ‘turn on’ the high voltage pack to in turn be able to charge the 12v battery.

you should be able to recharge the 12v battery manually from the wire pigtail which is located under the rear hitch cover. Once it’s recharged (assuming it isn’t totally dead/not useable at all) you should be able to start up your Rivian. Good luck!

Thanks for the explanation, but why can't the same charger be used to keep the 12V battery charged or even the brake regen? If an ICE engine can keep a 12V battery charged via alternator, then I refuse to believe the 12V battery can't be kept charged via a home charger and/or one of the four motors.

And, instead of wasting valuable software engineering resources reinventing the wheel creating apps that are already provided by Android Auto/Apple Car Play, how about allocating a few to detect when the 12V battery is getting weak BEFORE it fails!?

 

[ads75]

R1S w/12xxx VIN 25,291 miles and 174 miles to empty delivered 6/16/2923. SMH


Explain to me again why I got ZERO warnings beforehand and why the battery pack can't charge the 12V battery?

Your truck was delivered 900 years in the future, hence no warning.

On a serious note, it does suck for the 12v battery to die. Mine died last summer, took close to 3 weeks for mobile service to come and replace them. I think I had a brief warning light a couple weeks prior, that cleared almost immediately. I know some of the updates say they have improved the 12v warning, but obviously not for everyone.

 

[Steve A.]

you should be able to recharge the 12v battery manually from the wire pigtail which is located under the rear hitch cover. Once it’s recharged (assuming it isn’t totally dead/not useable at all) you should be able to start up your Rivian. Good luck!

Well, the tow truck driver just tried his booster pack on it and it at least woke up and opened the driver's side door, but that's all and it started sucking all the juice out of his booster pack quickly so it wasn't going to charge enough.

Also, since the booster pack only affected the driver's side locks and lights, I'm assuming it's one of the builds w/ the two 12V batteries; when it originally failed last night when I was leaving work and it briefly woke up as I approacd, only the driver's side headlight and light bar flashed then it went back to sleep.

So, last night when I called Rivian Service, the tow company said the driver on call did not have the tool to release the brakes and could I wait until today 8am-9am, and I said no problem since I was planning to come to work today anyway.

This am when the tow truck driver came out, I showed him the jump start procedure from the manual which is why he tried to jump it instead of crawling underneath it w/ the brake release tool in the pouring rain; however, when the jump start failed and he went to see how/where to use the tool, he said he didn't feel comfortable doing it since he hadn't done it before and one of the other tow truck drivers who *told* him how to do it was on anther call, so would it be ok to have him come out later. I said, no problem since I'll be here all day.

Once again, the seemingly simple things are complicated. #1WP

 

[jeeden]

Thanks for the explanation, but why can't the same charger be used to keep the 12V battery charged or even the brake regen? If an ICE engine can keep a 12V battery charged via alternator, then I refuse to believe the 12V battery can't be kept charged via a home charger and/or one of the four motors.

And, instead of wasting valuable software engineering resources reinventing the wheel creating apps that are already provided by Android Auto/Apple Car Play, how about allocating a few to detect when the 12V battery is getting weak BEFORE it fails!?

The charger and motors can't be used to keep the 12 volt batteries charge because the components don't exist there. Why don't they exist? Because of money, room, for components, and it's not necessary because it is not a normal operating case. This will be for the same reason they don't put alternators on the wheels of ICE engines just in case the battery dies and you want to roll it downhill to generate power and charge the battery.

Your example of an ICE engine keeping a battery charge with an alternator has the same limitation as an EV. And in ICE vehicle the engine must be running for the alternator to charge the battery. If the battery is dead the engine can't start and therefore the alternator can't run.

In an EV If the battery is dead the contacts to the high voltage can't be closed and the high voltage battery cannot charge the 12 volt battery.

In both cases you can jump start the car (as mentioned above) by providing enough temporary charge to the 12 volt battery to either start the engine or close the contacts and allow the alternator or the high voltage battery to charge the 12 volt battery. I would add in a ICE vehicle if you run the car enough with a battery that won't take charge and just use the alternator you'll often fry the alternator because it is not designed to put that much power out constantly and is made to maintain the battery.

They have been improving the warning for the 12 volt battery, but I would ask you how much warning you have gotten in the past about the 12 volt battery on your ICE vehicle dying? Usually you find out because the engine sounds a little slow when it starts on a cold morning if you're lucky.

I think it's been documented that Rivian got a poor batch of 12vbatteries at one point. The same thing has been documented in countless ICE vehicles and of course 12vbatteries wear out eventually. If I recall it was standard practice for Lamborghinis for many years to immediately remove the 12 volt battery from the brand new vehicles and replace them with new batteries because the ones they put in were from a supplier that were just awful.

As for the software resources for Apple CarPlay and Android Auto it's their choice. I love Android Auto, really I like Google maps not Android Auto, but I think that they're crown has started to lose a bit of it shine as a lot of vehicle manufacturers move away from them for cost savings performance or other reasons. While the maps and some of the audio might be a recreation of existing app capability in the Rivian software, certainly the entire stack that runs all of the car functions EV tech, and extras or not.

 

[COdogman]

I knew somehow this was connected to the lack of AA/ CarPlay.

 

[zpowell]

My 12V battery health is at 90% per Rivian. They can check. Does anyone know at what battery % the 12V batteries should be replaced?

I agree with the OP. Rivian has got to do better with warnings and ability to charge/service these 2 small 12V batteries. Changing batteries should be as simple as rotating tires or replacing wiper blades. NOT requiring tow trucks and service visits.

 

[Cycliste]

I just had my 12,000 km (7,500 mile) multipoint inspection done at Rivian. I’m not sure what that includes. I hope it helps identify items needing addressed to avoid ‘automotive component adventures’ like the OP.

 

[Steve A.]

The charger and motors can't be used to keep the 12 volt batteries charge because the components don't exist there. Why don't they exist? Because of money, room, for components, and it's not necessary because it is not a normal operating case.

Money being the #1 reason. Not a normal operating case? All batteries need charge and eventually fail. It's not an engineering impossibility to use the same charger to charge the battery pack and 12V batteries.

They have been improving the warning for the 12 volt battery, but I would ask you how much warning you have gotten in the past about the 12 volt battery on your ICE vehicle dying? Usually you find out because the engine sounds a little slow when it starts on a cold morning if you're lucky.

Yes. Every daily driver car, truck and tractor that I've owned over the past 38+ years I knew WEEKS in advance based upon how slow it turned over in the am. Low tech but obvious. Rivian software should do MUCH better than ZERO notice.

FWIW, I've NEVER had an ICE OEM 12V battery fail under 2 years and I've owned probably about 2 dozen ICE vehicles in the last 38+ years.

I think it's been documented that Rivian got a poor batch of 12vbatteries at one point. The same thing has been documented in countless ICE vehicles and of course 12vbatteries wear out eventually. If I recall it was standard practice for Lamborghinis for many years to immediately remove the 12 volt battery from the brand new vehicles and replace them with new batteries because the ones they put in were from a supplier that were just awful.

Exactly. Once again Rivian can do MUCH better if they know the specific batches of 12V batteries they used. That said, it's problematic being *proactive* when you're bleeding billions and losing $50k+ per vehicle sold.

As for the software resources for Apple CarPlay and Android Auto it's their choice. I love Android Auto, really I like Google maps not Android Auto, but I think that they're crown has started to lose a bit of it shine as a lot of vehicle manufacturers move away from them for cost savings performance or other reasons. While the maps and some of the audio might be a recreation of existing app capability in the Rivian software, certainly the entire stack that runs all of the car functions EV tech, and extras or not.

Professional software engineers are one of the most expensive costs. I've been one for 34+ years, so I know. Spending time on custom infotainment apps that are not as good as what's already available via AA/CP instead of improving critical operating software is not in the best interests of customers, AFAIC.

 

[Steve A.]

A lot of you seem to be confused. Yes the main battery can and does charge the 12v. It happens repeatedly without you noticing it. A battery has only so many charge cycles. The 12v battery is no longer able to hold an appropriate charge because it’s failed early or reached the limit of charge cycles it is capable of.
Your 12 battery in your ice vehicle does not get discharged as much as the one in an electric vehicle. Most things in an ice vehicle run off the spinning belts.
That’s why electric dies faster. Everything is electric so the battery is used more. This problem is not just Rivian. When my Tesla battery started to go the air conditioning which runs on the 12v couldn’t cool the car on a 90 deg day. Rivian just needs to get better at warning us.
Having more than one battery seems dumb at times but it’s a backup so you can actually get in your vehicle if the main battery is dead. They both need each other.

Ah...thanks for the explanation. Makes sense. Yes the 12V battery in an ICE vehicle is only used to start it and then the alternator takes over, while Gear Guard Gary is sucking juice all the time. ;-)

That said, still no excuse for ZERO warnings ahead of time esp. w/ two 12V batteries. What's the probability that both fail at the exact same time? Hope it's not due to some other electrical short or something.

 

[Steve A.]

I knew somehow this was connected to the lack of AA/ CarPlay.

If it's lack of software feature related, then yeah, I will continue to beat the dead horse! ;-)

That said, I hope they don't *try* to blame it on my @EV Sportline Apple CarPlay / Android Auto Smart Dash Screen install since it's wired to the fuse box and only wakes up when the R1S wakes up.

If they try, then I'm going to need some empirical evidence to refute from @EV Sportline.

 

[Cycliste]

I suggest Vehicle Health on the Rivian app should have some indicator of the 12 V battery health. 12 V battery health would also be nice on the Gauges view.

Should I just replace the 12 V battery every 3 years?

 

[Schneelafen]

5,600 miles, the 12v died after a charging overnight. 3 days ago. No warning. Came out 2 hours after last time driving with 66%, nothing left on. And it was bricked and a
message to get the 12v replaced.

 

[Steve A.]

5,600 miles, the 12v died after a charging overnight. 3 days ago. No warning. Came out 2 hours after last time driving with 66%, nothing left on. And it was bricked and a
message to get the 12v replaced.

Just curious. Did you run the last OTA update last week? Just wondering if it's related.

Sponsored