U0404 code

[jesilvas]

Wasn't able to find much about this specific code, just a lot of hard/bad shift threads.

A couple times, the service wrench has popped up while my wife is driving. And today it gave SHIFT SYS FAULT for the first time.
Drove home fine, no issues.
TorquePro didn't have codes, but I think it only scans PCM. Forscan Lite app showed U0404 on the TCM. I ran KOEO and KOER self tests, with no codes.
We have had hard shifts a few times on hard acceleration from a roll, but all else has been fine. Is this code related to the shifting issues or maybe some other problem, maybe a loose connector?

Thanks

2018 Expedition XLT 2wd, 99k miles

 

[Mr Big]

Wasn't able to find much about this specific code, just a lot of hard/bad shift threads.

A couple times, the service wrench has popped up while my wife is driving. And today it gave SHIFT SYS FAULT for the first time.
Drove home fine, no issues.
TorquePro didn't have codes, but I think it only scans PCM. Forscan Lite app showed U0404 on the TCM. I ran KOEO and KOER self tests, with no codes.
We have had hard shifts a few times on hard acceleration from a roll, but all else has been fine. Is this code related to the shifting issues or maybe some other problem, maybe a loose connector?

Thanks

2018 Expedition XLT 2wd, 99k miles

I can't answer the question about the code. But I can say resetting your pcm and tcm may help as it puts the vehicle back in factory settings and re-learns the driving habits of the driver or drivers. I was having sloppy and jerky shifting where the tranny would skip a lot of gears. I also had sluggish performance and lower than normal gas mileage. Being as I purchased a used Expedition, I reset my pcm and tcm and it made the performance, idling, mileage and shifting all feel great. I used FORScan to perform this. But there are videos on how to manually reset by disconnecting the battery.

 

[jesilvas]

Forscan Lite app also has the ability to reset them as well. I thought about doing that.

I also need to drop the trans pan and replace the filter and fluid; not sure if it's ever been done.