12V Battery Replacement Megathread

[HaveBlue]

Rivian vampire drains 1% of the HV battery per day (30% per month) trying to keep that little 18ah battery charged. It's a travesty. They've managed to lie to us by tweaking the firmware to show zero loss over night but leave it for days and you will see it quickly nose dive.

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[usulio]

Rivian vampire drains 1% of the HV battery per day (30% per month) trying to keep that little 18ah battery charged. It's a travesty. They've managed to lie to us by tweaking the firmware to show zero loss over night but leave it for days and you will see it quickly nose dive.

Also, a design that keeps waking up the vehicle and draining the little 18ah battery to upload data about you for Rivian's benefit, you pay the electricity bill.

 

[kallisti5]

Looking at the graphs here, it looks like Rivian tries to use as much of the 18Ah battery as possible before powering up the DC/DC converter to power the computers and charge the battery.

My guess is they're trying to reduce consumption on the main drive battery until the next time you plug in where they can charge the HV and low voltage batteries.

Fun follow up.. confirming that the 12v replacement button in RiDE doesn't actually do anything. I'm guessing I need to call Rivian service at minimum to clear the codes

 

[ksujeff99]

Looking at the graphs here, it looks like Rivian tries to use as much of the 18Ah battery as possible before powering up the DC/DC converter to power the computers and charge the battery.

My guess is they're trying to reduce consumption on the main drive battery until the next time you plug in where they can charge the HV and low voltage batteries.

Fun follow up.. confirming that the 12v replacement button in RiDE doesn't actually do anything. I'm guessing I need to call Rivian service at minimum to clear the codes

Have you successfully cleared the 12V warning message yet, without Rivian’s help? I have the Ohmmu batteries in my 2022 R1T, which worked great until the last software update changed the 12V diagnostics. I’ve had the 12V warning message ever since. Ohmmu even replaced both batteries under warranty. I was successful in getting the 12V error message to go away once, but it quickly came back a day or two later. No amount of disconnecting the HV & LV, RIDE menu 12V resets, or hard resets has worked.

If I knew it would solve the issue, I’d gladly give up some space in the frunk to mount a full size deep cycle battery

 

[RivLiam]

To bump this thread just got my 12v warning ironically a week after being in the service center for routine maintenance/break flush and I'm just out of warranty. There's (at least for now) a bit of a discount either because we're all complaining about it or if it's because I just asked them if I could buy two batteries off them and do it myself. All in $500(250 off).

 

[Lindsay VW of Dulles]

We've had a TON of 12V notifications after 2026.15.01 (Around 20 or so of our vehicles in inventory) Rivian Service has said the same.

 

[Dave Cundiff]

We've had a TON of 12V notifications after 2026.15.01 (Around 20 or so of our vehicles in inventory) Rivian Service has said the same.

I requested an R1S appointment for something else, and the AI chatbot in the Rivian App said they also want to deal with a critical 12V issue. Troubleis, this is only coming from the chatbot. The R1S isn't showing any warnings, and the support team at 855-RIVIAN-5 can't find any warnings attached to the vehicle.

I wonder if the AI chatbot is hallucinating 12V warnings. More shall be revealed....

Best wishes!

 

[UnsungZero_OldTimeAdMan]

I requested an R1S appointment for something else, and the AI chatbot in the Rivian App said they also want to deal with a critical 12V issue. Troubleis, this is only coming from the chatbot. The R1S isn't showing any warnings, and the support team at 855-RIVIAN-5 can't find any warnings attached to the vehicle.

I wonder if the AI chatbot is hallucinating 12V warnings. More shall be revealed....

Best wishes!

They don't only replace the 12V when there are warnings. They've had multiple pre-emptive campaigns to replace them. Collective info shared by the hive suggest latest software may contain different parameters for monitoring of the 12V. And what was previously deemed healthy may now be classified as "OK" (do nothing), "just OK" (no warning, but should be replaced), or "not OK" (warning, must replace soon).

If it's covered under warranty, no one should hesitate to have it done. If not covered (or owner chooses to take matters into their own hands), there's Ohmmu Sodium-Ion and few other aftermarket AGM alternatives discussed in another thread (plus soonishev.com's battery terminal adapters).

 

[Steve A.]

We've had a TON of 12V notifications after 2026.15.01 (Around 20 or so of our vehicles in inventory) Rivian Service has said the same.

My 2022 R1 that I bought from you in March literally got the 12V notification a day after 2026.15.01 was installed. SMH

I asked if for a mobile service appointment but they said it could just be a firmware update and I had to bring it in to the SC where they could run the firmware check although they ended up just replacing both 12V anyway since they were last replaced in 3/23 and were beyond end of life/warranty. The invoice said nothing about checking the firmware. SMH

FWIW, I went through two 12V notifications service calls at the same SC back in December where they kept it for the better part of two weeks for diagnostics between the two visits and they didn't end up replacing anything and blamed it on the OTA update; then a couple weeks later it left me stranded at Dulles airport where it was plugged in for 10 days to the L1 charger and had to get towed to the Dulles SC which is 2+ hours from home where they held it for over a week and eventually replaced the control module which they blamed for not reporting accurate voltages from the 12V.

So I reminded this SC of their failure to properly diagnose the problem last time with my R1S and if I got another 12V notification in the next 2 weeks would they be refunding me for the two new 12Vs since the rest the warranties still apply and he said he would "work with me" if that happens. We shall see.

Personally, I don't believe in coincidences and after 36+ years of professional software engineering experience and 3+ years of Rivian ownership and OTA updates, AFAIC the OTA update is the most likely suspect!

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