Hello everyone,
I am looking for some help with Forscan/recalibrating my 2015 F150 3.5 ecoboost to a new tire size. In the past I was able to get a 2 month trial of Forscan and able to make successful edits to the truck with the Forscan software always saving the original "As built" data configuration.

I was able to delete Sirius XM, turn off seatbelt warnings and activate "Bambi mode" to have high beams stay on and also make tire size changes to get a more accurate speedo after changing to bigger tires.

Previously the "stock/problem free" tire size was 275/65/R18 (2558mm In BCM), I then had a set of 285/75/R18 (2779mm) Goodyear Wrangler duratracs installed and the speedo was way off. With Forscan I edited the BCM configuration to read "2779" MM of circumference. Wrote the new size in, the truck accepted it but maintains a trouble code for "U04220" WITHOUT a wrench on the dash and NO check engine light on the dash. The trouble code cannot be cleared with Forscan or Bluedriver or standards Autel OBDII scanners. Drivability is unaffected, in fact the transmission shift points feel better than before I edited the tire size, however I cannot seem to clear that U04220 code even after trying the "PCM reconfiguration" step as suggested by other forum users. My truck does not have a TCM (6 speed 6R80 4X4) relearn option in Forscan and I have tried disconnecting the battery for several hours with no change and DTC U04220 still present. Currently most Ford dealers in my area are stumped and I haven't found any solution online except potentially BDX or SCT tuners which cost quite a bit without certainty of my problem being solved. Any help with Forscan wise?

Edit, I also tried using the Forscan excel Data sheet for my truck year with several other similar successful tire sizes used before by other users and all of the close sizes also maintained the U04220 "trouble code". The only way to have the code go away is to set the tire size parameters to "2558" or original tire size for the truck. Several hundred KM later and that code is still present please advise.

 

It won't go away unless you do as you stated in your last paragraph. I ran into this issue myself a couple of years ago and learned then that there is apparently a cap to the acceptable tire size in the 2015-2017 models. I don't recall if it was in Forscan's own forums or another F150 dedicated site that I came across this info, but I know many 2018-2020 owners do not have this issue. The way I resolved it permanently was eventually correcting the tire size within a few tunes I purchased. Before that, I set the size as high as I could without getting the U4220 code and dealt with being roughly 2 MPH off at highway speeds