Fuel-cell stack losing power and hydrogen leaks on the Nexo

Engine / equipment

First-generation Hyundai Nexo fuel-cell car

Period mentioned

2018–2024

Symptoms

When overtaking or on hills the car loses power for a few seconds and then surges; a power-limited warning from a fuel-cell system fault; hydrogen-leak warnings.

Possible cause described

Since August 2021 Hyundai has been checking the roughly 15,000 Nexo cars built up to July 2021 for faulty fuel-cell stacks and replacing them (electrive); the Korean press explains that a control-logic fault triggers the stack protection and cuts power, that the software is updated first and the stack replaced if the fault persists, and that a stack costs about 40 million won (10-year or 160,000 km warranty). In the US there were also recalls for the refuelling-inlet filter, which can come loose after refuelling and leak hydrogen (2019), for hydrogen sensors that may not detect a leak (2019–2021) and for the integrated electronic brake software (2019–2020).

Check for the garage

Ask Hyundai for the stack and campaign history by VIN; on the test drive, accelerate hard up a hill; park outside if a hydrogen warning comes on.

Cost cited in the source

A new stack costs about 40 million won (Korean press); covered by the 10-year or 160,000 km warranty.A rough figure from the original database, not an up-to-date quote.

Sources from the original database