This is my first post in this forum, thought by sharing our 12v battery adventure we could potentially help a few other Ioniq 5 owners out there
We purchased our Ioniq 5 2023 Limited AWD in July of 2023. Starting from Oct (4 months in) we started having 12v issues. It would die if I didn't drive the car for a day or 2. I bought myself a portable jump starter and survived a couple of months with that. But by Dec it was dying nearly every 6-8hrs. I would never see the yellow light (12v battery being charged by the big battery) at this point. The 12v was only getting charged when we were out driving the car. Battery Monitors would show a consistent trend of hourly downward spikes the battery recovers after 5-10mins but not entirely to the original level, and eventually, when this happens enough times in a row it would bring the battery down to < 10v and the car die. No dashcams or other after-market mods, not even USB cables plugged in.
After spending weeks on the phone with the dealership begging to get an appointment I was finally able to grab an appointment right before Christmas and drop the car off. The dealership performed the ICCU fix + replaced the old battery. They seemed pretty confident that the ICCU recall could fix the issue. We got the car back after a few days, and I put my Battery monitor back on. The battery looked a lot healthier I even saw the yellow 12v battery charging indicator light back on a few times. But within a day or two the battery monitor would confirm that the dips in voltage had not gone away - they occurred very regularly in an hourly interval or so, sometimes multiple times in an hour. But since we had the newer battery it was just dealing with these voltage drops a bit better. By the end of Jan 2024 (1 month since getting the new battery from the dealership) I was seeing 12v battery dropping down to 11.2-11.3v after staying parked overnight in the garage. It was pretty clear that the new battery would die on me in another month or two.
My dealership experience was pretty negative, they made me wait for weeks when living with the car was almost a hazard. And after the eventual servicing, they didn't clarify why this new 12v battery would solve the underlying problem, or what was causing this phantom power draw at such regular intervals. I remember seeing posts about frequent Bluelink activation causing 12v battery degradation - but I was also pretty sure that Hyundai claimed that they fixed this issue by limiting the number of remote requests that can be made by a Bluelink app to a fixed number per day. But at this point, I was ready to try anything sensible, so I went ahead and logged out of the Bluelink app, and changed my Bluelink password on Feb 7th.
Here is my Battery monitor chart for the last 15 days. The hourly 12v dips stopped almost immediately, that very night the DC to DC converter kicked in and charged the 12v battery for a while that night (and many more times since then) which I had only seen once since I received the new 12v battery.
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For the last 4 days things have looked a lot better, I hope I'm not jinxing it 🤞
I'm no expert in the underlying technology to manage the App and the remote actions but why a status check would draw that much voltage is beyond me. I did take two actions at the same time (i.e., logging out of the Bluelink account on my phone, and changing the password) I'm not sure whether one of those actions would have sufficed.
Anyway, thought I would share. Will post an update in a few more weeks.
We purchased our Ioniq 5 2023 Limited AWD in July of 2023. Starting from Oct (4 months in) we started having 12v issues. It would die if I didn't drive the car for a day or 2. I bought myself a portable jump starter and survived a couple of months with that. But by Dec it was dying nearly every 6-8hrs. I would never see the yellow light (12v battery being charged by the big battery) at this point. The 12v was only getting charged when we were out driving the car. Battery Monitors would show a consistent trend of hourly downward spikes the battery recovers after 5-10mins but not entirely to the original level, and eventually, when this happens enough times in a row it would bring the battery down to < 10v and the car die. No dashcams or other after-market mods, not even USB cables plugged in.
After spending weeks on the phone with the dealership begging to get an appointment I was finally able to grab an appointment right before Christmas and drop the car off. The dealership performed the ICCU fix + replaced the old battery. They seemed pretty confident that the ICCU recall could fix the issue. We got the car back after a few days, and I put my Battery monitor back on. The battery looked a lot healthier I even saw the yellow 12v battery charging indicator light back on a few times. But within a day or two the battery monitor would confirm that the dips in voltage had not gone away - they occurred very regularly in an hourly interval or so, sometimes multiple times in an hour. But since we had the newer battery it was just dealing with these voltage drops a bit better. By the end of Jan 2024 (1 month since getting the new battery from the dealership) I was seeing 12v battery dropping down to 11.2-11.3v after staying parked overnight in the garage. It was pretty clear that the new battery would die on me in another month or two.
My dealership experience was pretty negative, they made me wait for weeks when living with the car was almost a hazard. And after the eventual servicing, they didn't clarify why this new 12v battery would solve the underlying problem, or what was causing this phantom power draw at such regular intervals. I remember seeing posts about frequent Bluelink activation causing 12v battery degradation - but I was also pretty sure that Hyundai claimed that they fixed this issue by limiting the number of remote requests that can be made by a Bluelink app to a fixed number per day. But at this point, I was ready to try anything sensible, so I went ahead and logged out of the Bluelink app, and changed my Bluelink password on Feb 7th.
Here is my Battery monitor chart for the last 15 days. The hourly 12v dips stopped almost immediately, that very night the DC to DC converter kicked in and charged the 12v battery for a while that night (and many more times since then) which I had only seen once since I received the new 12v battery.
For the last 4 days things have looked a lot better, I hope I'm not jinxing it 🤞
I'm no expert in the underlying technology to manage the App and the remote actions but why a status check would draw that much voltage is beyond me. I did take two actions at the same time (i.e., logging out of the Bluelink account on my phone, and changing the password) I'm not sure whether one of those actions would have sufficed.
Anyway, thought I would share. Will post an update in a few more weeks.
