Navigation fault after upgrading SYNC 3.0 to 3.4 using CyanLabs Syn3 Updater

Ford SYNC 3 Support CyanLabs Update Support
, , , , , ,
1

Hi,

I have a Ford with a SYNC 3 Navigation APIM in the EU region. I upgraded the unit from SYNC 3.0 to SYNC 3.4 using CyanLabs Syn3 Updater.

After the update I get the following message on the SYNC screen:

“Navigation fault”
“Navigation is not functioning properly.”

The Navigation menu is present, but navigation is no longer functioning correctly.

I have attached the XML files from before and after the update, as well as a photo of the error.

Some information from the APIM interrogation:

VIN: WF0AXXWPMAHK58252
APIM address: 7D0
APIM OS part number: JR3T-14G381-AY
APIM has Navigation
Region: Europe
Installed navigation packages include:
JL7T-14G424-BA
JL7T-14G421-BA
JL7T-14G422-BA
JR3T-14G391-AE
JR3T-14G423-AB

One thing I noticed in the “after” XML is that the APIM still reports JR3T-14G381-AY as the OS/app package, which appears to correspond to SYNC 3.0.23219. I expected the APIM to report the SYNC 3.4 application package after the upgrade.

Could you please check the attached before/after files and let me know whether the APIM configuration, navigation configuration or map packages are incorrect and what I need to do to restore navigation?

Thank you!

SYNC Region: EU

Navigation Variant: Nav

Manufacturer Year: Pre MY20

Install Type: OEM

Old SYNC Version: 3.0.23219

New SYNC Version: 3.4.23188

Do you have a error message, if so what is it?
Navigation fault — “Navigation is not functioning properly.”

Update Method: CyanLabs Syn3 Updater

Syn3 Updater Version: 2.14.2.0 Stable

Syn3 Updater Documentation Read: yes

Syn3 Updater Log File

CYANLABS - SYN3 UPDATER - V2.14.2.0
Branch: Stable
Operating System: Microsoft Windows 11 Pro (2009)

PREVIOUS CONFIGURATION
Version: 3.0.23219
Region: EU
Navigation: False
Install Mode: Auto-Detect (autoinstall)
Install Mode Overridden: False
My20 Protection Enabled: Disabled / Not MY20

DESTINATION DETAILS
Mode: Drive
Model: USB SanDisk 3.2Gen1 USB Device
Size: 114.6GB
FileSystem: exFAT
Partition Type: MBR

AUTOINSTALL.LST
; CyanLabs Syn3Updater 2.14.2.0 Stable - Autoinstall Mode - Enforced Downgrade EU

[SYNCGen3.0_ALL_PRODUCT]
Item1 = APPS - 4U5T-14G381-AN_1552583626000.TAR.GZ
Open1 = SyncMyRide\4U5T-14G381-AN_1552583626000.TAR.GZ
Options = AutoInstall

FILES (1)
4U5T-14G381-AN_1552583626000.TAR.GZ (479.7MB)

LOG
[7/16/2026 12:12:27 PM] Selected Region: EU - Release: Enforced Downgrade - Map Version: Non Nav APIM
[7/16/2026 12:12:27 PM] Install Mode: Auto-Detect (autoinstall) Forced: False
[7/16/2026 12:12:27 PM] MY20 Protection: Disabled / Not MY20
[7/16/2026 12:12:27 PM] Formatting USB drive
[7/16/2026 12:12:27 PM] Re-creating partition table as MBR and formatting as ExFat on selected USB drive
[7/16/2026 12:12:34 PM] Checking Existing File: 4U5T-14G381-AN_1552583626000.TAR.GZ
[7/16/2026 12:12:37 PM] Validated: 4U5T-14G381-AN_1552583626000.TAR.GZ (Skipping Download)
[7/16/2026 12:12:37 PM] Preparing USB drive
[7/16/2026 12:12:37 PM] Checking Existing File: 4U5T-14G381-AN_1552583626000.TAR.GZ
[7/16/2026 12:12:37 PM] Copying: 4U5T-14G381-AN_1552583626000.TAR.GZ
[7/16/2026 12:12:54 PM] Validating: 4U5T-14G381-AN_1552583626000.TAR.GZ
[7/16/2026 12:12:56 PM] Copied: 4U5T-14G381-AN_1552583626000.TAR.GZ
[7/16/2026 12:12:56 PM] Generating Autoinstall.lst
[7/16/2026 12:12:56 PM] ALL FILES DOWNLOADED AND COPIED TO THE USB DRIVE SUCCESSFULLY!
2

You did a reformat with just the APP, you no longer have any maps installed.

Hence the NAV fault.

3

Thanks for the clarification. Yes, I understand now.

The sequence was:

  1. I originally had a factory SYNC 3.0 Navigation unit.

  2. I upgraded from SYNC 3.0 to SYNC 3.4 using Syn3 Updater.

  3. The update completed successfully, but after the upgrade I got a Navigation Fault.

  4. I then used Syn3 Updater’s troubleshooting/recovery options. It suggested a Reformat as the next action to try to recover the unit and avoid bricking it.

  5. I performed the Reformat with APP only.

  6. I now understand that this removed the maps, which explains the current Navigation Fault.

My main question is about the original Navigation Fault that happened immediately after the first 3.0 → 3.4 upgrade, before I performed the APP-only reformat.

What would you recommend I do now to properly recover the unit?

Should I simply create another Syn3 Updater USB with Navigation enabled and perform a complete reformat/update including the required APP + MAP + MAP_LICENSE + VOICE/NAVIGATION packages?

This is my first time updating SYNC 3, so I don’t want to try another option that could potentially make the situation worse. I would appreciate guidance on exactly which settings/install mode I should use in Syn3 Updater for my factory EU Navigation APIM.

I have attached the before/after XML files and my Syn3 Updater log if they are useful.

Thank you for your help!

4

Your first round was a reformat and you didnt select the right options.

Do a reformat, make sure you select the correct maps for install.

5

I bet he didn’t read the instructions.|100%x100%

6

And ensure that you do a master reset at the end.