cford716

I only did mine for about 1 hour. I haven't heard of anyone having to do it for more than that. However, I do have stock tires. I believe there are 2 different issues here causing the same error.

1. Those of use with stock tires and getting this error in position. (Which no dealership has been able to determine why.)

2. Those with larger tire which the systems dead reckoning (guessing) is overriding the more accurate satellite signal that it should be using as primary.

If this system allows the dead reckoning to override good GPS satellite information then this is truly a horrible program. What Ford was thinking I have no idea.

Mine is working now after the battery "fix" since the dealership couldn't find anything wrong.

windzurfer

Ok. Previously I had only disconnected for about 30 minutes each time. Apparently wasn't enough time to reset any cmos or whatever was keeping the info. So yesterday I left it off for about 4 hours and then went on a good long drive all over Houston with the wife Christmas shopping, meaning lots of turns and parking lots that would confuse the cap out of even the best gps. So it works flawlessly now. Amazing! Simply amazing that Ford can't figure that out. Realize I've only taken one good long trek with it yet so I'll see how it acts today.

I'm guessing from cford716 above that it should only have to be disconnected for about an hour. My Camaro only took about fifteen minutes when I had to pull the fuse since they didn't have a fix for the high/low octane maps on the SS. If you used low octane it would switch the MAC sensor to the low setting and wouldn't go back to high unless you pulled the fuse, effectively disconnecting the negative battery cable. This is the same way you reset the CIL when it comes on if you fix the issue yourself and don't have a diag tool to plug in and reset the light.

windzurfer

I'll scan in the email that the service guy gave me from the "ford engineer hotline" and post it. They talk about "steering wheel angle" which has me laughing every time I read it.

SofaKing

Just wanted to relay my results. I disconnected my negative battery cable and left it that way overnight. I just got back from a test run and the GPS is very accurate now. Since the truck was new, it has almost always shown the vehicle too far forward and at times off to the right as much as several blocks. I hope this easy fix lasts. I am surprised our Ford dealers service departments are not aware of this fix. I am sure they had disconnected the battery when I had it to them the last time, but they must not have left it disconnected long enough.

windzurfer

@ Sofaking, mine would seem to aleays be off to the left and most of the time would shpw.me traveling 45 degrees from my actual heading. I would be going due west and the compass at the top of the screen wpuld show NW.

Well, i got a call from the dealer service satisfaction person today asking how i enjoyed the service. I explained that all-in-all the experience was good but i was disappointed because although they could duplicate the problem they couldnt fix it. They were able to change the oil and rorate the tires (ida done it myself but figured they would have it for four days and it was time so I let them do it while it was there) and they should have given this to me at no charge as a gesture of "sorry" but they just dismissed it and told me it couldnt be fixed.

So i explained to her it was pretty sad that i got on the internet and found a possible fix in a matter of minutes and tried it and now have it working flawlessly. The fact that even Ford engineering couldnt take a good stab and figure it out. I have a BS in mechanical engineering and i have a really good appreciation of troubleshooting technique so its safe to say i was shocked they gave up without really looking at anything but software and mysterious angles because of a lift. The kicker?? She didnt even ask me what i did to fix it. I was only going to say it if she asked.

...i guess i better check the wheels actually got rotated and the oil cap was reinstalled. Lol.

windzurfer

alright, 12/14 I did the disconnect. It ran perfectly and flawlessly until today at about 6pm. then the indicator tracked off about 1/2 mile. What was different that I had never experienced before was it went inaccurate for about 2 miles of driving and eventually got itself out of my neighborhood lakes and got back on track. I'll have to see how it goes in the morning when I drive to work to see if it was just an anomaly. I hope it's not telling me that I need to disconnect the cable again because if I figure out it has to be done every week I'm still not going to be happy.

cford716

There has to be an issue with the software that uses the other inputs it get from the vehicle and preferences that over a satellite signal. If is has a good signal there should not be any positioning problems. Strange system. Hope Ford figures this out soon.

Its a shame that your dealership took the easy way out and said it must be your lift. Too bad others like myself have had the same problem with stock trucks.

h2ouup2

It appears to be a software issue. What seems to be happening is once you lose SAT signal for an extended period of time the system gets hung in a loop and dead reckoning takes over even when the GPS signal is available again.

Software not releasing memory is not new and this looks like a classic example.

So unhooking the NEG cable on the battery for an hour clears out the memory and allows the GPS code to take priority again. If you see your GPS off afterwards, but then get back on track, it's because your dead reckoning is still off, but it wasn't on long enough to get stuck in the loop. Once you got the GPS back the system switched.

So the question Ford needs to ask is what is causing the NAV to get stuck in a loop and/or not release? Why does it get off when new tires are installed?

My understanding is it doesn't happen to the 2012 just the 2013.

It's really a shame that Ford can't find a fix, but the Forums here can.

byte

GPS take awhile to boot up and get a fix... depending on how long they have sat before the drive .. it can take 5-10 minutes to acquire the data needed to get accuracy... some times of the day the satellites may not be over head to get a good fix... it takes 6 satellites to get a decent location.. 12 is normal... In the time the gps is gathering data, the computer would use speed to estimate where you are.


Does this happen in the first 10 minutes of driving???

byte

Certain times of the day you may not have enough satellites above you to get a decent fix on location... try this to see when the bad times are for you area..


http://stellarsupport.deere.com/en_U...arfire-status/


http://satpredictor.navcomtech.com/


I notice the bad times for signal too when my tractor is steering itself down the field