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Question: Rivian 12V warning: drive to service or request mobile help?

PistonTraveler4Community StarterJul 17, 20262023 Rivian R1T Quad-MotorNYC / Long Island
2023 Rivian R1T Quad-Motor, about 1,200 miles. Got a 12V-related service warning and the truck otherwise wakes and drives normally. For people who've dealt with low-voltage issues, did you risk driving to service or treat it like a potential bricking issue? I'd rather test this logically than start replacing parts.
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14 replies

V8Geek89Community StarterCommunity StarterJul 17, 2026permalink
Charge curves lie if you don't match starting SOC and temp. Match starting SOC and battery temp if you're comparing 2023 Rivian R1T charge sessions. I'd do that before spending real money. I'd want that in writing, not as a promise. If that fails I'll eat the diagnostic fee.
EuroWrench18Community StarterCommunity StarterJul 17, 2026permalink
Low-voltage gremlins will strand you even with a full pack. Try a second charger before blaming the 2023 Rivian R1T — site sharing and pack temp change the curve a lot. That's where I'd start. Happy to compare notes if your setup is different. Might be overthinking it, but I'd rather overthink than overspend.
PistonTraveler4Community StarterCommunity StarterJul 18, 2026permalink
OP update: scanned the 2023 Rivian R1T again and still only have the one pending code, no new lights. Only after sitting overnight so far.
TireDriverCommunity StarterCommunity StarterJul 18, 2026permalink
Don't clear the alert just to make the screen pretty. Leave the alerts on the 2023 Rivian R1T so service can see what you saw. Then you'll know the next fork. A shop burned me once by skipping that step. Only after sitting overnight so far.
TireDriverCommunity StarterCommunity StarterJul 19, 2026permalink
I hear you, though I'd still want a second check. On the 2023 Rivian R1T, I'd get the 12V/DC-DC side checked even if the traction pack looks fine. That's where I'd start. On “rivian 12v warning: drive to service or,” that was the fork that mattered for me. Had a similar mess a couple years ago and that's what finally sorted it. Checking again after work.
OldSchoolWrench20Community StarterCommunity StarterJul 18, 2026permalink
Charge curves lie if you don't match starting SOC and temp. Match starting SOC and battery temp if you're comparing 2023 Rivian R1T charge sessions. That's where I'd start. Keep sale price, fees, and rate as three different conversations. I already checked the easy fluid levels.
WrenchShopper67Community StarterCommunity StarterJul 18, 2026permalink
Yes, with one caveat: On the 2023 Rivian R1T, I'd get the 12V/DC-DC side checked even if the traction pack looks fine. Then you'll know the next fork. On “rivian 12v warning: drive to service or,” that was the fork that mattered for me. If they can't show the line item, I assume it's hiding. If your situation is the opposite, ignore me. Trying not to diagnose from the couch.
TireDriverCommunity StarterCommunity StarterJul 19, 2026permalink
Fair point. Counterpoint: Match starting SOC and battery temp if you're comparing 2023 Rivian R1T charge sessions. That's where I'd start. Had a similar mess a couple years ago and that's what finally sorted it. This is me being the wet blanket on purpose.
PistonTraveler4Community StarterCommunity StarterJul 18, 2026permalink
OP update: scanned the 2023 Rivian R1T again and still only have the one pending code, no new lights. Cold start is when I can actually reproduce it.
RustBuilderCommunity StarterCommunity StarterJul 18, 2026permalink
Don't clear the alert just to make the screen pretty. Leave the alerts on the 2023 Rivian R1T so service can see what you saw. Then you'll know the next fork. If it doesn't change the out-the-door or the repair estimate, it's noise. Next check is the cheap one I can do in a driveway.
WrenchShopper67Community StarterCommunity StarterJul 18, 2026permalink
Low-voltage gremlins will strand you even with a full pack. Try a second charger before blaming the 2023 Rivian R1T — site sharing and pack temp change the curve a lot. That's where I'd start. Verbal 'we'll take care of it' is not a plan. I've seen both outcomes, which is why I'd test instead of assume. I'd rather look cautious in this thread than stuck later.
PistonTraveler4Community StarterCommunity StarterJul 18, 2026permalink
I went back under the 2023 Rivian R1T and it only happens after a heat soak, not on a cold start. I'm keeping receipts and dates in one folder.
QuietRider85Community StarterCommunity StarterJul 19, 2026permalink
Don't clear the alert just to make the screen pretty. Leave the alerts on the 2023 Rivian R1T so service can see what you saw. I'd do that before spending real money. If you share a photo of the worksheet, easier to sanity-check. I'd rather be boring and correct. No warning lights, which is why I'm documenting it.
OldSchoolWrench20Community StarterCommunity StarterJul 19, 2026permalink
Don't clear the alert just to make the screen pretty. Leave the alerts on the 2023 Rivian R1T so service can see what you saw. Then you'll know the next fork. This is from a 2023 Rivian R1T in NYC / Long Island with 1,200 miles. Keep sale price, fees, and rate as three different conversations. If the story changes I'll post the new data.
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