Hyundai Sonata Hybrid / Kia Optima Hybrid Revised 47 kW Lithium Polymer Battery (2013-2016)

Reported failures, each from a source listed below, as of October 7, 2026.

• Owner complaints NHTSA lists under the Hybrid Propulsion System component for the Hyundai Sonata Hybrid, Kia Optima Hybrid, by model year: 2013: 2 · 2013: 5 · 2014: 1 · 2014: 1 · 2015: 2. These are all hybrid system complaints, owner reported and unverified, not only battery faults, as of 2026-10-07.
• Hyundai TSB 23-HC-001H-1 (August 2023, 2011-2015 Sonata Hybrid) says the HEV safety plug or the power relay assembly (PRA) can set DTCs P0A0D, P1B25, P1B76 or P1B77, and tells technicians to check these parts before diagnosing the hybrid battery itself. (static.nhtsa.gov: MC-10241797-0001.pdf, 2026-10-07)
• Hyundai's Sonata Hybrid bulletin points 2013-2015 cars to service campaign 994 (HEV safety plug and fuse inspection/replacement) before the power relay assembly is diagnosed. (static.nhtsa.gov: MC-10241797-0001.pdf, 2026-10-07)
• Kia TSB ELE273 and warranty extension WTY029 cover inspection and replacement of the high-voltage battery safety plug fuse (or main fuse) on 2013-2016 Optima Hybrids built September 27, 2012 to July 22, 2015, including replacement of non-genuine fuses, with DTCs P1B77 and/or P1B25. (static.nhtsa.gov: MC-10230486-0001.pdf, 2026-10-07)

Symptoms

• Hyundai TSB 23-HC-001H-1 lists a cluster message reading 'Hybrid System Warning! Safely stop and Do Not Drive', a Check Engine light and a blinking service (wrench) indicator on 2011-2015 Sonata Hybrids with a safety plug or PRA fault. (static.nhtsa.gov: MC-10241797-0001.pdf, 2026-10-07)
• The same Hyundai bulletin describes no 'EV Ready' mode or a Ready light that blinks on and off, and a car that will not move from a stop or whose engine will not start. (static.nhtsa.gov: MC-10241797-0001.pdf, 2026-10-07)
• Kia's WTY029 owner Q&A tells 2013-2016 Optima Hybrid owners to see a dealer if a 'Hybrid System Warning' message appears or if they see smoke or smell a burning odor, which can point to a failed safety plug fuse. (static.nhtsa.gov: MC-10222376-0001.pdf, 2026-10-07)
• Kia's Optima Hybrid (2012-2016) emergency response guide says the battery is cooled by an electric fan drawing cabin air through an intake on the rear package tray, and that a blocked intake can let the hybrid battery overheat. (morongocsd.specialdistrict.org: Kia+Optima+HEV+2012-2016+ERG.pdf, 2026-10-07)
• A keyword search of the 5 Hybrid Propulsion System complaints NHTSA lists for the 2013 Kia OPTIMA HYBRID finds that 3 mention warning light, 5 mention stalling or shutting down (complaint text is owner-reported and unverified; as of 2026-10-07). (NHTSA complaints, 2013 Kia Optima+Hybrid, 2026-10-07)

Hyundai's 2021 Warranty Coverage Guide lists lifetime hybrid battery coverage for the original owner of 2013-2015 Sonata Hybrids, 10 years/100,000 miles for later owners, and 10 years/150,000 miles for SULEV/PZEV cars in California-emission states, while Kia's 2022 bulletin WTY029 states that 2013-2016 Optima Hybrids carry a 10-year/100,000-mile Hybrid System Limited Warranty and extends coverage of the high-voltage battery safety plug fuse to 15 years/150,000 miles. (static.nhtsa.gov: INRD-PE21010-15928.pdf, 2026-10-07)

How battery warranties work.