Hyundai hybrid battery repair — Sonata, Ioniq, Elantra and Tucson

If you're outside coverage, or the dealer says the fault isn't covered, come back to us and we'll tell you what we can do.

Most of what's written about hybrid battery repair online is about Toyota's nickel-metal hydride packs — including the idea that you can swap a couple of weak modules and rebalance the pack. That approach is far less often viable on a lithium-polymer pack.

• Lithium cells age differently, and the pack's management system is more tightly integrated with the cells than on an older NiMH pack.
• Module-level repair is possible on the 2011–2019 Sonata Hybrid — that pack is nine bolted modules and we sell them individually — but it is a more demanding job than a Prius. The replacement has to be charged to match the group it joins before the pack is closed.
• Parts sourcing outside the dealer network is harder than it is for Toyota, which affects both cost and lead time.
• Our published $500–$900 reconditioning range generally does not apply to these vehicles. Ask before assuming.
• Diagnosis still works the same way in principle: measure it properly before anyone recommends a repair.

• A hybrid system warning or check engine light on the dash.
• Reduced electric-only running, or the engine holding on where it used to shut off.
• Fuel economy declining over weeks or months.
• Reduced power under hard acceleration.
• On the Ioniq and other plug-in-adjacent models, a noticeable drop in electric range.
• 12V battery symptoms — which on a newer car are far more likely than a failed traction pack.