Tlrmade

just un connect the cables and turn the lights on and let the temporary power drain then re connect battery?

FordIVTteam

Hey all,

LXCoupe is correct. Changing to a bigger tire size can affect the GPS performance. It relies on something called "dead reckoning". If your vehicle loses its GPS connection for any amount of time, it will recalibrate your current position based on the tire rotation. Your dealer may be able to modify the tire circumference settings in your GPS.

Shaay

Turbo Kidd

I just upgraded to a 34' tire, however, I corrected the size with my tuning.....Now, my GPS is all wacked out. It shows the red triangle about a 1/4 off the roads I am traveling on, hence my GPS doesn't know where the hell I am.

Any thoughts? Will pulling the negative cable help in this case?

Spiky

Yes, it needs to reset separately from the tuner changes you made. Apparently.

justjimmy

I disconnected the battery for a while and that seemed to work.

Wicked46

I have a 14 with the same issues. I re-calibrated the speedo but I guess that isn't good enough. I'll try disconnecting the battery like you mention and see what that does for me.

justjimmy

You'll need to disconnect it for at least 45 min. Like was mentioned earlier, it needs to flush the memory.

Wicked46

It worked!

Tallyman89

Guess I need to disconnect cables too. Hate the GPS and have the A7 card. As is, not even close to my needed destination. Stock tires.