NHTSA Complaint #11700895 — 2025 RIVIAN R1S

SUMMARY OF PROBLEM: Vehicle experienced sudden uncontrolled acceleration and deceleration while driving on busy road with family as passengers on November 16 2025. Vehicle provided no warning before loss of control occurred. Created immediate risk of collision and serious injury. DETAILED DESCRIPTION: On November 16 2025 at approximately 5:25 PM ET, my 2025 Rivian R1S experienced sudden uncontrolled acceleration and deceleration while driving on a busy roadway. The vehicle began accelerating and decelerating erratically without driver input, creating immediate risk of rear-end collision or loss of control. No warning lights or messages appeared before the incident. The vehicle displayed "Thermal Fault Detected" and "Coolant Level Low" messages only after the erratic behavior began. This incident occurred with my family in the vehicle and created serious risk of injury or death. I was forced to have the vehicle towed. PRIOR RELATED INCIDENTS: This is not the first safety issue with this vehicle. Service Request SR-RAB3DU1AM documents "Emergency Braking Mistakenly Triggered on Regular Roadway" from August 29 2025 that remains unresolved in Rivian's system. The vehicle has required multiple service visits for thermal and cooling system failures at only 15000 miles. MANUFACTURER RESPONSE: Rivian service center claims rodent nesting caused thermal system failure leading to loss of vehicle control. If correct, this indicates critical design flaw - environmental factors should not be able to compromise vehicle control systems without warning or failsafe mechanisms. Vehicle lacks adequate: - Warning systems for thermal degradation before catastrophic failure - Failsafe mechanisms to prevent loss of control - Protection of critical systems from environmental factors SAFETY CONCERN: If thermal system damage can cause sudden loss of vehicle control without warning, this represents unreasonable safety risk. Other R1S vehicles may be at risk of similar failures.