Tire size, gear change, and speed limiter

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Posts: 1
Joined: Sat Jul 02, 2016 7:54 pm
Vehicle: F150, V8, 5.0L, 2013

Tire size, gear change, and speed limiter

Post by SkyMaster » Tue Jul 05, 2016 1:10 pm

Vehicle: 2013 Ford F150, RWD, 5.0 V8

I started with an SCT tuner and was able to successfully change all these parameters but wanted to test these same options with ForScan so I returned the tune to stock with the SCT tuner and plugged in my ELM327

All of these options are available in the Body Control Module and are easily changed and written to the BCM

After these changes I received two DTC’s P160A and U0422 both of these point to what appear to be a BCM too PCM configuration mismatch

Upon road testing this morning I found the Speedometer and Tachometer did not match the gear and tire change and the speed limiter was still enabled

Has anyone else run into this issue?

Looks like the “real” values for these options are stored in the PCM and the changes need to be made in both the BCM and PCM

On a positive note, Dark Mode works great 8-)

Posts: 1
Joined: Tue Jul 05, 2016 10:46 pm
Vehicle: Ford F-150, ecoboost, 2011

Re: Tire size, gear change, and speed limiter

Post by BKR89 » Fri Aug 26, 2016 4:50 pm

I ran into the same problem changing tire size on my 2011 F-150. I was able to clear the U0422 code but am still working on the P160A code. I also turned on my DRLs so that may be triggering the P160A code. I'll deactivate the DRLs and see if that clears the code.

Just curious, what is the Dark Mode you referenced?

Todd Ector
Posts: 94
Joined: Mon May 18, 2015 1:33 pm
Vehicle: 2004 F150 XLT , 5.4 3v sohc 300hp
Location: Elbow, Saskatchewan, Canada

Re: Tire size, gear change, and speed limiter

Post by Todd Ector » Sun Oct 23, 2016 12:24 am

Dark Car or Dark Mode is a feature used by police agencies. Essentially it disables the door switches so that the interior lights don't turn on when you open the doors of the vehicle. Older vehicles had a physical connector you unplugged, since the early 2000's it's a software switch same as DRL's.

Posts: 1
Joined: Wed Nov 30, 2016 1:28 am
Vehicle: 2011 Ford F150 3.7L

Re: Tire size, gear change, and speed limiter

Post by coneheaded » Wed Nov 30, 2016 11:05 pm

Regarding tire size changes, I've had the P160A code since I bought my truck (2011 F150). Bought used from a dealer, they replaced the tires before delivery and put on 235/75-17's when the stock size was 265/70-17. Buggers . I didn't notice until the next day. I know they changed the tire size in the bcm because I have the maintenance records.

So, even from the dealership that code was set. Today I programmed 265/70-17's in and still had the code. In forscan, that size corresponds to 2440mm (0988 hex). My as built data shows 098A which is 2442mm. So I just went out and tried that with forscan along with the proper checksum and the P160A code is gone...

Thanks to Dordogne for the post about setting tire sizes, couldn't have fixed it without that.

Posts: 2
Joined: Fri Apr 05, 2019 2:53 pm
Vehicle: F150 XLT 3.5 ecoboost 2011

Re: Tire size, gear change, and speed limiter

Post by 11_f150_eco » Wed Apr 10, 2019 4:38 pm

I just put 4.11 Gears in and no one could get the change in the BdyCM Module Configuration axle ratio to take affect. I received the P0160 code this is the process I used to fix it:
Make the needed change in the Module Configuration.
Reopen the main screen in Configuration and Programming
The first line is PCM Relearn. Click that then Start button. Follow promps (this will have you turn key of and on and takes a few minutes.)
If you have other codes address them
Then Clear Codes.

It worked for me

Another note: It is much easier to make changes in the Module Configuration screens than in the AS BUILT screens, if your parameter to change is there.

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