StrangePenguin
New Member
Yesterday morning I plugged in my 2020 Clarity (11900 miles) in the garage (120V charger). An hour or 2 later, I went out and unplugged it (it was about 70% charged). It was cool in the garage, 65 or 70, and while charging it was not making any excess noise. Right after I unplugged it, the engine fan under the hood came on like a jet engine. I've never heard it so loud before. After fretting about it for a couple minutes, fan still running, I tried plugging it back in. The fan immediately stopped and it went back to charging. Another hour later I repeated the cycle: unplug, radiator fan immediately going into overdrive, wait a minute, plug in, fan stops and goes back to charging.
At that point I unplugged it (fan came back on again), got in, and tried to start it. It wouldn't start and flashed various things on the dash -- it thought I was in accessory mode, it wouldn't let me change gears. (Although I think the fan did cut off, maybe when I first tried to start it.) It kept saying "Accessory mode -- press Start twice to turn off" so I kept trying that. It also started cycling through every error known to man (Tire Pressure Monitor, Brakes, Power System (?), etc). Eventually I was able to turn it fully off again, and then it sat quietly in the garage as I prepared to take it into the dealership.
When I was ready to take it in, voila it started ok and I was able to put it in gear. However it did go through a litany of errors on the dash again (Tire Pressure Monitor, Brakes, etc) that continued as I drove it to the dealership. The check engine light was on as well.
The dealer said that they can't find anything actually wrong with it. Their printed report says there were "a lot of miscommunication codes related to battery condition". They cleared the codes and it seems to be fine now. They noted that they found 2 cases of the same problem reported on Tech Line Forums, and that in those cases the problem did not recur.
Hopefully this is a once off problem that will not happen again. Seems like basically the computer needed a reboot, so to speak. I was curious if something like this has happened to anyone else.
At that point I unplugged it (fan came back on again), got in, and tried to start it. It wouldn't start and flashed various things on the dash -- it thought I was in accessory mode, it wouldn't let me change gears. (Although I think the fan did cut off, maybe when I first tried to start it.) It kept saying "Accessory mode -- press Start twice to turn off" so I kept trying that. It also started cycling through every error known to man (Tire Pressure Monitor, Brakes, Power System (?), etc). Eventually I was able to turn it fully off again, and then it sat quietly in the garage as I prepared to take it into the dealership.
When I was ready to take it in, voila it started ok and I was able to put it in gear. However it did go through a litany of errors on the dash again (Tire Pressure Monitor, Brakes, etc) that continued as I drove it to the dealership. The check engine light was on as well.
The dealer said that they can't find anything actually wrong with it. Their printed report says there were "a lot of miscommunication codes related to battery condition". They cleared the codes and it seems to be fine now. They noted that they found 2 cases of the same problem reported on Tech Line Forums, and that in those cases the problem did not recur.
Hopefully this is a once off problem that will not happen again. Seems like basically the computer needed a reboot, so to speak. I was curious if something like this has happened to anyone else.