HECU Can Error Code &/or car battery draining?
November 20, 2021 1:57 PM

I have a 2016 Kia Forte 5 LX 4 cylinders 2.0 L that appears to have a draining battery overnight. More below.

As stated above- I took the car to AutoZone to run a diagnostic test on the system which turned up a C1616 error code, "HECU can bus off".
They also ran a check on the battery and the alternator; the battery is 100% charged (after a jump earlier today- jumped the car earlier this week as well) and the alternator appears to be fine too.

I just had the oil changed, oil filter replaced, and cabin filter replaced, and the next day started having these issues with the car not turning over. When it's dead, there's simply no activity; the engine won't turn over at all. Never had any problems until the day after the oil change, probably a sheer coincidence but seems worth mentioning.

There is no corrosion on the battery, which is about 2.5 years old, and there are no check engine lights on. I checked through some of the passenger side fuse box fuses and all are ok, as well as did a random check of fuses in the engine fuse box.

I looked around the car's interior for any kind of "parasitic drain" type issues, but there is nothing obvious.

I am the very shadiest of shadetree mechanics, so I am just running through the obvious stuff first. Any ideas on what might be drawing the battery down? Car has about 41k miles on it and I've been following regular maintenance procedures Thank you!
posted by erattacorrige to Technology (3 answers total)
Did you take it to the mechanic who did that initial work? Sounds to me like they left a wire disconnected somewhere, something simple that's causing a steady battery drain. I would absolutely not write that off as a coincidence.
posted by Lady Li at 11:23 PM on November 20, 2021


A few follow up questions I've gleaned from Google-fu, if you are going to try this yourself:
- is your car subject to this recall for fire hazard from the hecu, and has the work been done?
- this error message, per googling, can be caused by an open or a short in the HECU CAN bus. It also could be an old message triggered by the service and be fine now, the way to tell seems like it would be by clearing the error and seeing if it comes back. Next steps would be to hunt down that schematic and see where the CAN cables connect, make sure none of them are unplugged, etc.
posted by Lady Li at 11:32 PM on November 20, 2021


Oh the cabin filter installation is free, which is why I had it done simultaneously as the oil change.
I don't think that the recall is valid for my 2016 Kia forte.
I am the second owner of this car.
posted by erattacorrige at 9:03 AM on November 21, 2021


« Older What should I do in East Anglia?   |   Come on everybody Mousercise! Newer »
This thread is closed to new comments.