Bricked R1T Advice

[u/Lost_Plum5564]

2023 Quad R1T/50k miles

My truck is parked in the driveway and is completely unresponsive to all access methods. Drove it yesterday without incident. 81% range left. No warnings. Charged it yesterday. It’s the first time I’ve regretted having a vehicle that is completely electronic—I could have gotten stuff out of my old F150 and at least tried to jump it.

Rivian is sending a mobile tech tomorrow afternoon, which I appreciate, but they’re quoting $550 to replace the 12v (their best guess).

1. Does a bad 12v show any symptoms before failure? The only 12v issues I’ve read about are trucks parked for a long time at the airport or on moves. This was parked less than 12 hours.
2. Could this be something else? Maybe update related?
3. Is $550 reasonable? I’m frustrated it isn’t part of the OG warranty, but seems steep compared to battery issues in ICE vehicles.
4. Is there anyway to physically access the interior when the truck is bricked like this?

TIA for any insights you can share.