jetchaser

2014 FX4. I've had an SCT X4 tuner for about a year now (in anticipation of bigger tires) and have performed adjustments with factory settings (No custom tunes yet). No problems at that point. This past week in an earlier post, I showed off that I bought larger tires 295/60/20 Coopers and added my level kit. It came out awesome. So I used the programmer to update the revolutions per Mile to correct the speedometer. That all worked out great and the speedometer is within 2 mph of a handheld GPS. Good by my standards. But I used the Navigation and the map shows the truck running parallel to the road or highway I'm on. It shows that I'm driving in the middle of no where. Sometimes it syncs up, but as soon as I come to an intersection and turn right or left, the GPS is off again. I used the programmer to go back to factory settings but still the same results. What do you think it could be? I have an A7 GPS card in. I used this as a good excuse to go ahead and buy an A9 but I'm skeptical this will fix the problem.

Any suggestions?

Dave

brimee

Dave Z

Dave,
You need to perform a master reset, the procedure is in your owners manual.

https://owner.ford.com/support/how-t...ter-reset.html

The GPS in your truck relies on your tire rotation when it goes into DR (dead reckoning). Your tuner only calibrates your speedometer, not everything to do with tire size.
Another Dave, A&P, IA

jetchaser

Thanks! I did this and hopefully it helps. All these years of searching level kits and tires brands, I must of missed that bit of information. I love this site!

Also an A&P, IA!!

jetchaser

Uh oh. The master reset didn't work. Still off after the test drive. Now disconnecting the battery. We'll see if that does the trick.

Kkline

jetchaser

I unplugged the battery last night and reset everything. Back to normal now. Thanks for the help everyone!

Dave Z

Your SD card is only the database for the navigation. It has the streets, roads, and points of interest locations. It does not age, but that is how you update your database.
These cards cost about $150 from the dealer but you can also get them on ebay for a considerable savings. The A9 version just came out.