KIA / Hyundai EGMP Platform ICCU precautions (Ioniq 5, EV6, etc) - Page 1
Forum section: electronics / general

author: thex
author_rank: Newbie
timestamp: August 12, 2025, 02:24:16 pm
content: Hi,as I have just bought an Hyundai Ioniq 5 based on the EGMP platform which seems to be prone to failures of the ICCU (Integrated Charging Control Unit) I'm very interested what you think about options to reduce the probability of getting affected by this.The issue seems to be to high inrush current when the charging of the 12V battery is initiated. (https://static.nhtsa.gov/odi/rcl/2024/RCMN-24V868-9385.pdf)The fix seems to be to gradually ramp up power when initiating a charge cycle of the 12V battery. (Software only fix)Now I'm wondering how I could minimize the inrush current in other ways.I was thinking that maybe replacing the 12V battery with a LiFePo4 battery with a good BMS which limits the inrush current. But that currently is only speculation as I can't find specs for inrush currents on these batteries.What do you think?Any other ideas to limit the charging inrush current of the 12V battery?

author: Stray Electron
author_rank: Super Contributor
timestamp: August 12, 2025, 03:46:49 pm
content: I'm sure that there are plenty of folks here that can make suggestions but I think that if you do ANYTHING to any of the electronics in your car, even just opening the box to look at the circuits, that you're going to void every warranty of every kind that your vehicle has. So if it were me I would pass on this idea, at least until all of the warranties have expired. The one thing that you could do and probably get away with it would be to put a strong surge suppression system to your household's AC system to prevent a power surge from reaching your car's charging system. Your charging system may already have good surge suppression built in so this may not help but OTOH, it won't harm anything either.A friend of mine bought an electric KIA Kona several months ago and I just rode in it for the first time this past weekend. He charges his from a home solar system and AFIK hasn't taken any special precautions.

author: coromonadalix
author_rank: Super Contributor
timestamp: August 12, 2025, 04:05:37 pm
content: adding coils / inductance in serial should alleviate some problems,but for sure as mentioned earlier, you'll void warranty ... or the dealer would not like it ...there are recalls for that problem, you need to check in your countryhttps://insideevs.com/features/752768/hyundai-kia-genesis-iccu-failure/https://www.carsdirect.com/automotive-news/recalls/hyundai-ioniq-iccu-recall-explained

author: woofy
author_rank: Frequent Contributor
timestamp: August 12, 2025, 04:12:37 pm
content: I've had a Kia EV6 for the last 2.5 years - no ICCU problems at all.I'd say forget about it and leave it to Hyundai to fix them if you do get any problems.

author: thex
author_rank: Newbie
timestamp: August 12, 2025, 06:44:01 pm
content: Sure I‘m totally aware of voiding warranty if I change anything.To clarify as some replies suggest it was not completely clear:The problem does not have to do anything with charging the cars high voltage battery. The problem seems to stem from the car trying to charge the old school 12V battery which upon charger activation shortly takes a really huge inrush current.The software fix via ramping the voltage already seems like a good approach but you still hear about some failures with updated ICCUs. I’m also well aware that the problem is to some extent overhyped otherwise I would not have bought the car.I work in automotive software and know for a fact that if a manufacturer can do a recall with software only he will always do it, even if a physical solution would only cost 5ct per customer.I was just thinking what kind of options I would have to limit the current with easy reversible measures like a different battery. (Which also would be hard to trace if we are talking warranty but let's not go there and focus on the technical aspects instead)