r/IoniqEV

So I wanted to know more about the internals of my Ioniq, and spent way too much time on it ever since I got my WiCAN Pro last summer, so I could see all my car’s secrets live in Home Assistant. It was slow going and difficult at first, but I finally have something to show for it (though it didn’t help with the WAF, I regret to inform you).

The tool I built that finally helped me make progress faster now allows anyone with a WiCAN to scan their car (Ioniq or otherwise) and do reverse engineering in “easy mode”, because it’s a CLI and therefore coding agents like Claude Code/OpenCode etc. can directly use it to talk to your car, scan it, capture a set of responses and do some crunching and clever analytics to derive meaning from them.

Here’s a tiny set of the things I found that weren’t yet known for these cars:
- OBC AC Input voltage and current (helpful for diagnosing AC charging issues)
- Individual wheel speed sensors (owners will know why this is helpful to know)
- A whole suite of HVAC sensors
- Vehicle speed, motor RPM, remote control of lights/blinkers/horn/trunk/VESS and other fun stuff.

Now I’ve done a lot of this on my Ioniq 2017, so the profile for it is pretty complete at over 200 verified parameters (I started with less than 10 a year ago). But I reckon owners of the facelift (38 kWh) might still get value out of this tool (I expect a lot of the 2017-2019 model PIDs carry over 1-to-1). I can’t wait to see what you folks are able to do with this, and I hope it helps keep our magnificent Ioniqs on the road for many more miles (and kms).

Go see the Ioniq profile on GitHub for the full list of ECUs and all the gory details I found on the car’s modules and adjacent systems, and read the docs if you’re curious about the tool itself and would like to contribute (I would personally be very thrilled if you do!). Thanks for reading all the way! 🙏

Most manuals online are for the hybrid version, took me years before I finally found one for the EV so I want to share it with you folks. It has info on everything about the car, from body work, seats, power windows, mirrors to HVAC (heat pump system) to the BMS and all the HV stuff. Send me a DM for a copy - If enough interest (and if allowed by moderators) I’ll add a permanent link. It says it’s for the 2019 model but it matches perfectly for my 2017 vehicle, pretty sure it’s 99% the same so it should match 2018 as well.

EDIT: Reddit prevents sharing the link through DMs. You can find it here: https://en.hyundaiclub.eu/manual_download.php?id=5195

UPDATE: of course after all this it charged last night, the first night out of 3!!!
Maybe it just won’t charge if it doesn’t think it can reach the charge limit during the hours set, I don’t know
Anyway it’s charged, finally

Can anyone tell me why this won’t start a charge at midnight and end at 6am ?
I’m using the granny charger and I gather it gives about 5% an hour so should be plenty of time to reach 80% from 60%
But for 3 nights now it just won’t start a charge
2021 premium

Hi all, changes the gearbox oil and put new magnetic bolts. Odometer is 25.000km. Took me 2 hours with my friend.

Hi, I have a 2017 Hyundai Ioniq 28 kWh with around 119,000 km.
When I accelerate hard, I hear a short clunk/knock once, then it’s quiet. The same happens when I brake hard with strong regen. With normal acceleration/braking there is no clunk, and when braking hard in Neutral there is no clunk either.
No grinding, rattling or continuous noise. I attached a video where you can hear it.
Has anyone had the same issue? Was it the reduction gearbox, driveshaft/CV joint, or motor/gearbox mount?
Also, if it needs repair: does anyone know a good workshop in Austria, preferably Vienna or the surrounding area, that can repair Ioniq EV motors/reduction gearboxes instead of just replacing the whole unit?

#Update 1:
I did some more testing today.
- The clunk only happens with hard acceleration or strong regenerative braking.
- If I accelerate and brake gently, there is no clunk at all.
- If I shift to Neutral and brake hard, there is no clunk.
- I drove about 90 km today at speeds between 30–140 km/h. No grinding, rattling, humming or other gearbox/motor noise.
-I also found an old inspection report: the front right rear control arm bushing was replaced in December 2025, so work has already been done in that area.