[Trazza]

Love my i30 but have had two occasions where the overheat indicator erroneously showed up when starting a cold car.

First time,  I was able to reset it by shutting car off and restarting 30 seconds later. First service check from Hyundai found nothing wrong. 

Last incident it did not reset until fourth shut-down /restart cycle. 

The car is due for first annual check up.

What do I need to do to address this successfully at the service centre??

TIA (I just DRIVE the blasted thing. .  .    Your asking me to fix it as well??! 😁)

[beerman]

Sounds like a gremlin in the wiring. Problem with that is that it is easy to pass off with the dreaded 'Tested no fault found' which is a comment so common it must have a hot key 

Mention it at your service, and if they can't find anything, try calling in as soon as you can after it happens, there might be a fault code they pick up.

Of course disregard everything I said if the resident Hyundai Guru pops in and gives you differing advice. 

[The Gonz]

Get some video evidence using your phone next time it happens. Then march in there and demand a fix..Hard to refute that kind of proof. Good luck!

[Trazza]

Get some video evidence using your phone next time it happens. Then march in there and demand a fix..Hard to refute that kind of proof. Good luck!

I did get the forensic evidence, Gonz. Guess great minds think alike. 📷😉