Originally Posted by Spart

Seems people have gotten this DTC when having the dealer program other tire sizes (the dealer is limited to what's in IDS obviously)

http://www.ford-trucks.com/forums/12...ger-tires.html

I wonder if this means that there's another value somewhere else that needs to jive with 726-12-01? Or maybe it's not that big of a deal.

Originally Posted by Spart

Is it possible there's an additional line in the ABS that needs changed to match the BCM?

Originally Posted by Spart

To be clear a DTC is not the same thing as a warning light. This is not turning people's dummy lights on, just throwing a diagnostic code that can be read with the same tools we use to program the as-built.

More likely that the PAM simply relies on it for some calculation, I would think.

I think what's happening here is that the speedometer and odometer rely only on 726-12-01, and it's used to interpret the data coming from the speed sensor in the transmission.

Other systems that use both the transmission's speed sensor in addition to the ABS/ESC speed sensors at each wheel are having an issue because the data coming from the transmission now doesn't jive with the data coming from the wheel sensors.

So the speedometer/odometer is being corrected for odd tire size, but not the ABS/ESC/whatever systems. We've got to figure out if/how we can correct their math as well. Or if it's something that can be safely ignored.

ETA: is it possible that whatever module is interpreting the wheel speed sensor data "learns" an algorithm for making that data match what comes from the transmission speed sensor? If that was the case, would we need to reset the learned values to it could relearn with the new value in 726-12-01?

Originally Posted by Spart

We don't know if the DTC is a huge issue yet. Might just be the price of doing this for "free." Maybe we just need to find another line somewhere else to edit to make it match the one in 726-12-01.

Here's some of my brainstorming from the big FORScan thread:

Originally Posted by Spart

Oh I get it, me too! I'm revisiting the as-built data trying to find other areas that seem to vary with the factory-equipped tires.

Has anyone with a 2011-2014 tried changing 726-45-01 yet? I'd be curious if you guys get a DTC as well, since in those years the Raptor was available, and the difference in tire size is much larger and easier to spot.

ETA: When will we be able to get a VIN for a 2017 Raptor so I can pull the as-built for that?

Originally Posted by k.b.

A couple of guys in the 2017 raptor order release date thread have vins PM one of them, I think Delmer has one

Originally Posted by Max91

Ok here's what I have. I adjusted the speedo using the calculator and Forscan. Yes, I got the DTC in Forscan but none in OBDwiz. I took the truck to AutoZone and had them connect their scanner and got the same results...None.

I wondering if Forscan is just not happy with that code..

Originally Posted by Spart

I think maybe the generic ODB readers might be skipping over or are not capable of reading certain codes? It's not a code that turns on the CEL/MIL/SES or whatever light.

I found this on another forum on U0422:



I'm not convinced it's worth worrying about. It might be that it's just warning about an inconsistency that isn't critical to any system. Maybe the ABS checks it's wheel speed sensor inputs against the speed sensor in the transmission as a way to check for erroneous data from the wheel sensors and vice versa? Could be that simple.

Originally Posted by dannofx4

and this works for 09-14 as well?