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Ioniq 5 broken.
Posted: Wed Aug 28, 2024 9:16 pm
by Joeboy
SWMBO was heading out this evening. EV no starty, called Hyundai breakdown. AA guy there in 15 minutes
12V battery flat, 5A charging rate on the 12V with 4A draw from vehicle with nothing on once jump pack applied.
Battery was sitting at 5V only so it's done in. Will jump start tomorrow if flat again and drop at dealers. First breakdown in 2.5yrs and 34,000 miles.
Re: Ioniq 5 broken.
Posted: Wed Aug 28, 2024 9:34 pm
by Oliver90owner
I carry my lidl jump starter in the glove drawer for just that scenario.
The 12V battery is known to be a weak link. Particularly the original.
Some say to change it for an AGM type - but i’m not entirely sure if that is best as the float voltage is very slightly different. Likely makes no odds but I would be checking with Hyundai before replacing it.
If there is 50W (or is it 20W?) being drawn, there may be a fault somewhere. If it set up to the blue link app that might be one area to investigate. That is known to be a problem if being continually operated by unwanted/unnecessary signals, I believe.
Re: Ioniq 5 broken.
Posted: Wed Aug 28, 2024 9:35 pm
by Moxi
JB my EV6 had a recall recently because there was a batch of vehicles made with a faulty component that can result in the 12volt battery not charging - bearing in mind Kia and Hyundai are stable mates it might be that there’s a similar recall on your car that wasn’t picked up due to the way you bought it maybe ? The recall might not have made its way to your address? Just a thought
Moxi
Re: Ioniq 5 broken.
Posted: Wed Aug 28, 2024 10:27 pm
by Moxi
Can’t find a specific uk recall but deffo an issue
https://eu.usatoday.com/story/money/car ... he%20NHTSA.
America but affects the I5, maybe a chat with the dealership?
Moxi
Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 12:33 am
by Oliver90owner
My I-5 had the recall for the ICCU update/replacement. It was, I believe, a software update and a fuse change on mine. Done and dusted in a couple of hours or more (I was waiting at the dealership) back in late May.
I put a battery monitor on mine quite early on, but removed it before it went in for the recall. Time I fitted it again. It records voltage against time and can be accessed via its bluetooth app.
Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 7:26 am
by Mart
There was definitely a problem and recall for 12V batts in 2023. Also questions as to whether the problem has been fully resolved.
Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 7:29 am
by Joeboy
Oliver90owner wrote: ↑Thu Aug 29, 2024 12:33 am
My I-5 had the recall for the ICCU update/replacement. It was, I believe, a software update and a fuse change on mine. Done and dusted in a couple of hours or more (I was waiting at the dealership) back in late May.
I put a battery monitor on mine quite early on, but removed it before it went in for the recall. Time I fitted it again. It records voltage against time and can be accessed via its bluetooth app.
I'll buy a jump pack, cheers for that. Car was in on 23rd July for an ICCU update... Bad fortune or irony?
Can.i have a link to the battery monitor you used?
The car is on its original 12V battery.
Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 8:10 am
by Joeboy
Looks like it will be a fortnight before they can even look at the car. No courtesy car until fault diagnosed, smashing!
Reverting to the transit connect back up vehicle (diesel).
This jump pack ordered.
Had to jump it again this morning.

Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 9:25 am
by richbee
Joeboy wrote: ↑Thu Aug 29, 2024 8:10 am
Looks like it will be a fortnight before they can even look at the car. No courtesy car until fault diagnosed, smashing!
Reverting to the transit connect back up vehicle (diesel).
This jump pack ordered.
Had to jump it again this morning.
That's pretty crap service - and not great the battery failing after only 2.5 years
Re: Ioniq 5 broken.
Posted: Thu Aug 29, 2024 10:01 am
by Oliver90owner
That's pretty crap service - and not great the battery failing after only 2.5 years
Lots of lead/acid batteries fail soon after the warranty expires. Nothing new there. Modern battery chemistry is not kind for situations where the battery is not kept fully charged at all times. Every discharge and recharge cyle adds up.
The factory 12V batteries on the I-5 are a well known weak link. Mine is coming up to two years old. I’ve never used the blue link app but often used to play the radio while parked - often until the car warned of auto shut-down.
Blue link has created a problem for some, at times, where the system keeps getting activated unnecessarily, multiple times. Leaving the car at below 20% state of charge, for the traction battery, was another reason for a flat battery (they now apparently recharge the 12V battery until 10% SOC). Dash cams, which don’t completely shut down, are just one more possibility for a parasitic load with the car off.
Mine was like one of these. Plenty of options with a search on epay for 12V battery monitor. I bought four at the time - one for each car battery and two for monitoring the batteries which run my chinese diesel heaters.
https://www.ebay.co.uk/itm/315693335365 ... R6L4_dSzZA
If the battery proves to be dead and is the only reason for the fault, I would be changing it soonest.