2022-23 Hyundai Ioniq 5 software update bug bogs down Eco mode

2022-23 Hyundai Ioniq 5 software update bug bogs down Eco mode

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There's quite a bit of debate about how many lines of code it takes make the modern car run. A former GM engineer said the Chevrolet Volt contained 10 million lines. The number "100 million lines" has showed up everywhere from an IEEE article in 2009 to a Porsche article in 2021. In 2016, Ford said its new F-150 contained 150 million lines. Jaguar Land Rover said in 2019 that autonomous vehicles will need 1 billion lines of code. So no matter the number, there's no debate that the amount is "a lot." Which means there's no debate that there are going to be more unintended software errors as vehicles get more modern. Jalopnik found out the 2022 and 2023 Hyundai Ioniq 5 AWD trim caught a bug after a factory update in December 2022 known as Service Campaign T9Q. In this case, a revision billed as an improvement to battery preconditioning had the effect of making Eco mode practically unusable.


Jalopnik's experience happened with a press car — an Ioniq 5 that Hyundai loaned to the outlet for a week to review. The crossover was fine in almost all of its driving modes. In Eco, though, it became "unacceptably slow," the writer discovering this when making a left turn across traffic. Flooring the throttle didn't get acceleration above a crawl until the car reached around 15 or 20 miles per hour.

Turns out some owners have been complaining about this ever since a dealer-installed software update late last year. On December 29, a member at the Ioniq Forum started a thread called "Preconditioning update, disappointing change to power curve in Eco." Some updated cars get handicapped, like one owner who wrote, "After the update, even when flooring it getting to 60 takes over 10 seconds." Even the least-potent Ioniq 5 shouldn't need much more than 5 seconds for the task. However, plenty of other owners have said their cars show no change after the new software.