Nav Issue with Change of Wheels and Tires

Hi folks. I have a 2015 GT Premium with 50th anniversary package. I live in the Northeast and I bought a set of 18" OEM 5 spoke 2015 Mustang rims for the winter months in place of the 50th anniversary 19" rims.

Summer set up: 255/40 R19 (Option Mustang 19" wheels/tires)
Winter set up: 235/50 R18. (Stock Mustang 18" wheels/tires)

The combination is nearly identical in overall diameter (27" vs 27.3") and circumference ( 84.9" vs 85.6"). So the speedometer difference is about 0.5-0.7 MPH difference which is acceptable.

The issue is that the SYNC2 navigation system doesn't function too well. It starts out OK but after about 4-5 miles the car icon (arrow) comes off the road, the system seems to lose sync and the nav system becomes non responsive and useless. After another 3-5 miles is syncs back up only to drift off again.

To confirm I don't have a GPS module issue I put the original 19" set up back on and everything returned to normal.

Is there an easy way for me to reprogram the car when I do the winter / summer tire swap-over so I can use the Nav all year round? I heard the aftermarket tuners (Bama / SCT) have speedo calibrations for changing rear end ratios etc, but thats overkill for what I am trying to do. I'd hate the get the "stealership" involved since they probably will want to either sell me a new car or change the entire system.

Anyone else see this? solve this? :headbonk:

Thanks

That is the strangest thing! the tires should still be in tolerance. Are the TPMS sensors registering?

Folks. I solved it!! Disconnected the battery for 20 min. Tried it again and the Nav stayed synced up with the 18" wheel set up. Must have reset history or the dead reckoning algorithm of the GPS module.

Bottom line: If you change rims/tires and you have Nav. Disconnect Battery for 20 min to reset the system.

Assuming I will have to do the same when I go back to the 19" summer set up.

There is a reset in the menu, would that be better?

Very strange. Never heard of that and there are countless people swapping wheels on/off throughout the seasons. I'm assuming many with nav. That's is really weird...

Oh well, glad you worked it out.

emba129 said:

Folks. I solved it!! Disconnected the battery for 20 min. Tried it again and the Nav stayed synced up with the 18" wheel set up. Must have reset history or the dead reckoning algorithm of the GPS module.

Bottom line: If you change rims/tires and you have Nav. Disconnect Battery for 20 min to reset the system.

Assuming I will have to do the same when I go back to the 19" summer set up.

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You are assuming correctly. F150s with sync2/MFT do the thing. Apparently tire size affects the nav system. I change my summer/winter ties on my F150. My summers are 275/75/20 and my winters are 265/75/17. Huge size difference and throws my nav in a frenzy. :shrug:

Anyway f150forum.com have several threads on the issue.

I have navigation. I can't say that I've ever used it... Google Maps is still better.

wildcatgoal said:

I have navigation. I can't say that I've ever used it... Google Maps is still better.

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And this is exactly why I don't understand why anyone opts for navigation in their cars anymore. I've got multiple friends with nav systems in their vehicles, and whether it be BMW, Ford, Jeep, Chevy, etc, no manufacturer makes a nav system that even comes close to what any smartphone with Google maps can do.

That is really odd. The 2 setups are very close to each other so there should be no brain farts. I cant tell you how many sets I have changed on my car but if the battery reset did it, that is fantastic and am happy you resolved the issue.

Damn, I just went to 19's from the 18's. I will have to check next time I go out.

Ive changed my tires no issues with nav, i use nav and like it!

Dominant1 said:

Ive changed my tires no issues with nav, i use nav and like it!

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Same size?

Fordever said:

Same size?

Click to expand...

no different size