2018 Sonata limp mode

I had the software update for the knocksensor done about a month ago in my 2018 Sonata GLS. 2.4l . Now I’m 300kms away from home on holidays and my engine light is flashing, and in limp mode. Being Canada day my home dealer isn’t open. I phone tomorrow morning. I only have 15,900kms on it , bought it a year ago. Wiring harness? Or engine? Or I’m hoping something not too drastic. Any ideas?

Post the diagnostic codes. They will explain why the engine has been placed in limp mode. That’s where to start. Sometimes auto parts store will read them with their own scanner tool as a customer service.

Usually it’s the harness. I had this issue in February.

I will, just nothing open here on Canada Day.

How long did you have to wait for a new harness?

Post the engine configuration too, that car came w/5 different options. Do you have a turbo version?

2.4l . I will post what the dealer tells me …

There’s very few service bulletins on the 2018 Sonata non-turbo, non-hybrid 2.4L engine. Nothing that would obviously cause this symptom. I’m seeing no reference to harness problems either, but that info may not appear in the service bulletin database yet.

I seen to recall a discussion here about this issue, a software update results in needing a new wiring harness. Doesn’t apply specifically to the Sonata, but to some Hyundai engine configurations. You might try the forum search feature. Upper right on this page. Here’s one I found

I had this problem in March. Needed a wiring harness. Took about a month. That was in Fl.
When I serviced it May, told that it took longer for them to get the part. Hope it’s better now.

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OP, when you had the software update done, did the dealership shop folks explain that it might cause this side-effect?

No they did not. I belong to a couple of Hyundai forums, and have been reading about some of the problems that have popped up after the software update.

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I did inform the service advisor that this problem has occurred to others after the update, she told me she hasn’t heard about this before.

I’m not sure how to interpret that. It’s possible I suppose the problem hadn’t yet appeared at that particular service center. It would be a shame however if they knew and didn’t inform you, as you might could take some pro-active strategies to circumvent this occurring far from home-base.

Well early morning my home dealership is getting a phone call. I’m on holidays 300kms away, they WILL be addressing this situation.

3 weeks or so. Not a big deal, they gave me a loaner.

They will have to get my car to their dealership, I’m not paying for a 300+ km tow lol. Phone call tomorrow morning will let me know what and how to solve this issue.

What if they gave you loaner there, for you to use for your return trip. Then you drive the loaner back in a month to pick up your repaired car? That might be an option to float. It would also give them an incentive to finish the job quickly.

Your warranty is good at any Hyunsai dealer in your country.

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Sonata on the way to dealership 40 kms away. Service manager said it looks and sounds like wiring harness problem, and he has one on stock. So tomorrow morning is the latest he is able to get it looked at first thing on the board. It will take about 1 1/2 hours he said. Fingers crossed…

Thanks for the update. Keep us informed.